Timing properties of XB 1254--690
$^{1}$CRESST and X-ray Astrophysics Laboratory
NASA/GSFC
Greenbelt
MD 20771
USA
$^{2}$Department of Astronomy
College Park
MD 20742
We analyze archival Rossi X--ray Timing Explorer ({RXTE}) Proportional Counter Array (PCA) data of the low mass X--ray binary (LMXB) system XB 1254--690. We calculate colour-colour diagram, hardness-intensity diagram and power spectra of this source, associate its broad low-frequency timing features with the portions of the colour-colour diagram, and establish that XB 1254--690 is an atoll source. This will be important to correlate the timing and spectral features of this dipping LMXB with its various states, which may be useful to understand LMXBs in general. We find the source always in the high intensity banana state, which may explain why $\sim 1$ Hz ``dipper QPOs'' have never been observed from XB 1254--690. We also report a suggestive evidence of millisecond period brightness oscillations at the frequency $\sim 95$ Hz during a thermonuclear X--ray burst for the first time from this source.
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\title[Timing properties of XB 1254--690]{Timing properties of XB 1254--690}
\author[Sudip Bhattacharyya]{Sudip Bhattacharyya$^{1,2}$\thanks{E-mail:
sudip@milkyway.gsfc.nasa.gov}\\
$^{1}$CRESST and X-ray Astrophysics Laboratory, NASA/GSFC, Greenbelt, MD 20771, USA\\
$^{2}$Department of Astronomy, University of Maryland,
College Park, MD 20742, USA}
\begin{document}

\date{}

%\pagerange{\pageref{firstpage}--\pageref{lastpage}} \pubyear{2002}

\maketitle

\label{firstpage}

\begin{abstract}
We analyze archival Rossi X--ray Timing Explorer ({\it RXTE}) Proportional Counter 
Array (PCA) data of the low mass X--ray binary (LMXB) system XB 1254--690.
We calculate colour-colour diagram, hardness-intensity diagram and power spectra
of this source, associate its broad low-frequency timing features with the
portions of the colour-colour diagram, and establish that XB 1254--690 is an atoll source. 
This will be important to correlate the timing and spectral features of this
dipping LMXB with its various states, which may be useful to understand LMXBs
in general. We find the source always in the high intensity
banana state, which may explain why $\sim 1$ Hz ``dipper QPOs'' have never been
observed from XB 1254--690.
We also report a suggestive evidence of millisecond period brightness oscillations at the
frequency $\sim 95$ Hz during a thermonuclear X--ray burst for the first
time from this source.
\end{abstract}

\begin{keywords}
methods: data analysis --- stars: neutron ---
 techniques: miscellaneous --- X-rays: binaries --- 
X-rays: bursts --- X-rays: individual
(XB 1254--690)
\end{keywords}

\section{Introduction}

XB 1254--690 is a persistent low mass X--ray binary (LMXB) system (Griffiths et al. 1978),
that exhibits energy dependent intensity dips (Courvoisier et al. 1986) with the binary orbital 
period ($\sim 3.88$ hr). This modulation of soft X-ray intensity is believed to be caused
by structures above the accretion disc (White \& Swank 1982). This is 
possible only if the dippers are high inclination systems, so that the
line of sight passes through these structures. Therefore, dippers provide
an opportunity to constrain the properties of the upper layers of accretion discs (and the
photoionized plasma above them; Jimenez-Garate et al. 2003) in LMXBs.
However, in order to understand the nature of these X--ray emitting and absorbing 
components, it is essential to
identify various states of the source, and to correlate the observed timing and spectral
features with these states. But, no detailed timing properties of XB 1254--690
have previously been reported. Moreover, the nature 
of this source is not yet established
(e.g., Z, atoll, etc.; see, for example, van der Klis 2004; 
Kuulkers et al. 1997; Wijnands et al. 1998;
Homan et al. 2002; Agrawal \& Bhattacharyya 2003).
Here we note that, although Gladstone, Done, Gierli\'nski (2006)
have recently included XB 1254--690 in the list of atoll sources, these authors have not
given a discussion to justify this, have not shown a separate colour-colour diagram (van der Klis
2004; Belloni \& Hasinger 1990; Olive, Barret, Gierli\'nski 2003; 
Jonker et al. 2000) of this source, and have not done timing 
analysis using the {\it RXTE} PCA data of XB 1254--690 in order to find the nature of this source.

XB 1254--690 also exhibits type-I X--ray bursts (Mason et al. 1980; Courvoisier et al. 1986).
These bursts are produced by thermonuclear burning of matter
accumulated on the surfaces of accreting neutron stars (Woosley \&
Taam 1976; Lamb \& Lamb 1978), which shows that XB 1254--690 contains a neutron
star. During many such bursts from some other LMXBs, the combination of rapid stellar rotation and
an asymmetric brightness pattern on the neutron star surface gives rise
to observable millisecond period brightness oscillations (Strohmayer \& Bildsten 2006).
The frequency of these oscillations gives the neutron star spin 
frequency (Chakrabarty et al. 2003).
Moreover, this timing feature may be useful to constrain stellar structure parameters
(Bhattacharyya et al. 2005; Nath, Strohmayer, Swank 2002), 
and to understand thermonuclear flame spreading
on neutron stars (Bhattacharyya \& Strohmayer 2005; 2006a; 2006b; 2006c).
However, until now,
burst oscillations from XB 1254--690 have never been reported, and the spin
frequency of the neutron star is not known. Therefore, the detection of
these oscillations from this source will be very useful.

In this paper, we perform timing and spectral analysis of the {\it RXTE} PCA data of XB 1254--690,
calculate the colour-colour diagram (van der Klis 2004), correlate broad timing features with 
different portions of it, and establish that XB 1254--690 is an atoll source.
Moreover, we find a suggestive evidence of oscillations from one type-I (thermonuclear)
X--ray burst. In \S~2, we describe
our data analysis procedure and results, and in \S~3, we discuss the implications of these
results.

\section[]{Data Analysis and Results}

The LMXB system XB 1254--690 was observed with {\it RXTE} in the years (proposal numbers) 
1996 (P10068), 1997 (P20066), 2001 (P60044) and 2004 (P90036). In 2001, the source was
observed both in May, and in December. We have used these proportional counter array (PCA)
instrument data to calculate the colour-colour diagram (CD; Fig. 1), and
hardness-intensity diagram (HID; Fig. 1), and to perform timing studies.
For the first two, we have always used PCA Standard 2 mode data, while for the third one
we have used PCA Good Xenon data (except for 1996 observations, for which we have used 
PCA Event mode data with about 16 $\mu$s resolution). The PCUs 0, 2 and 3
were reliably on during these observations, and we have used the data from these PCUs (and only
from the top Xenon layers to increase signal-to-noise) to calculate the CD and HID.
We have defined the soft and hard colours for the CD (the intensity for the HID)
as the ratio of the background-subtracted counts (background-subtracted count) in the
channel and energy ranges mentioned in Table 1. These definitions for various observations are 
very close to each other, and also very similar to those used by Muno, Remillard \& Chakrabarty (2002;
hereafter MRC). This will facilitate the comparison of our results with those of these authors.
However, the gain settings of PCUs change from time to time, and small gain shift happens 
even in the same gain epoch. As a result, artificial relative differences among CD (and HID) tracks
of various observations may occur. We have corrected this effect by using the PCA data of 
Crab pulsar/nebula, as the Crab colours can be supposed to be constant (Homan et al. 2002;
van Straaten et al. 2000; Altamirano et al. 2005). 
We have scaled the colours of the XB 1254--690 observation sets (except the one during
May, 2001) mentioned in Table 1 to correctly compare them with those of the May, 2001
observations. We have utilized the Crab data at the closest time (but in the same gain
epoch) to each of the five observation sets to do this (see, for example, 
Homan et al. 2002).

In order to explore the nature of XB 1254--690, first we have calculated a typical X--ray flux from this
source by fitting spectra with a model. The $2-20$ keV average flux is 
$\approx 10^{-9}$ ergs cm$^{-2}$ s$^{-1}$. 
Considering an estimated bolometric correction factor $\sim 2$, and assuming
(1) the source distance in the range $8-15$ kpc (Motch et al. 1987), (2) the neutron star mass
in the range $M_{\rm x} = 1.4-2.0 M_\odot$, and (3) solar hydrogenic abundance, 
we have found the source luminosity in the range $\approx 0.05L_{\rm Edd} - 0.25L_{\rm Edd}$,
where $L_{\rm Edd}$ is the Eddington luminosity.

We have, then, compared our CD (Fig. 1) with that of MRC.
Fig. 1 of MRC shows that the flaring branches (FBs) of Z sources have hard colours less than 0.3
(except for GX 17+2). As the hard colour of XB 1254--690 is always greater than 0.3, 
this indicates that if this source is a Z source, it
was not in an FB state. Besides, during these observations
the source showed frequent flares, which are not usual for the 
other two states (normal branch and horizontal branch) of Z sources.
Therefore, it is not likely that XB 1254--690 is a Z source.
Moreover, the typical luminosities
of Z sources are close to the Eddington luminosity (van der Klis 2004), and hence much higher
than the luminosity of XB 1254--690. Therefore, we conclude that XB 1254--690 is not a Z source.

Fig. 1 of MRC shows that the hard colours of atoll sources are always greater than 0.3
(except for GX 13+1). This, and especially the observed hard colours of the banana branches of 
atoll sources (see MRC) strongly indicate that XB 1254--690 is an atoll source, and
it was in the banana branch during all the observations (see Fig. 1). The following
findings also suggest that XB 1254--690 was in banana branch during these observations: 
(1) the source covered a large part of its CD track in a few hours, and
(2) the source hardened as its intensity increased (i.e., possibly went into upper banana (UB)
state from lower banana (LB) state; van der Klis 2004).

To confirm the identification of the banana state of XB 1254--690, we have computed and
fitted the power spectra of the source during low intensity and high intensity for each
of 2001 and 2004 data (Table 2). The chosen 2001 data sets are from the same ObsID, which shows
that the source intensity can significantly change with a timescale of hours. Both the power spectra
from these low intensity and high intensity data sets can be well fitted with a `constant+powerlaw'
model (no. 1 \& 2 of Table 2). The `constant' describes the Poisson noise level, 
and the `powerlaw' describes the very low frequency noise (VLFN). The detection of the
latter noise strongly indicates that the source was in banana state during the
2001 observations (van der Klis 2004). Moreover, the strength of the VLFN increases
with the intensity and the hardness of the source. This, and the disappearance of the VLFN
during the low intensity state of the 2004 data (Table 2 and Fig. 2) are also consistent 
with banana state properties of atoll sources (van der Klis 2004). We also note that
the power spectrum of the low intensity 2004 data can be well fitted with a `constant+Lorentzian'
(Fig. 2). The `Lorentzian' indicates a broad hump, or alternatively a band-limited noise (BLN;
van der Klis 2004). 

We have detected five type-I (thermonuclear) 
X--ray bursts from XB 1254--690: one from 1996 data and four from
2001 data. All of them are non-photospheric-radius-expansion bursts with the peak count rates
in the range $\sim 500-800$ counts s$^{-1}$ PCU$^{-1}$ (for all the detector channels). 
None of the 2001 bursts shows
significant millisecond period brightness oscillations. However, we have found suggestive evidence of
burst oscillations during the rising portion of the 1996 burst.
In the inset panel of Fig. 3, we show the first power spectrum 
that we have calculated using 16 $\mu$s event mode data and a 1 s time interval
(i.e., 1 Hz frequency resolution). This interval starts at the time
when the burst count rate starts rising sharply.
We have found a candidate peak at $\sim 95$~Hz with the power of $\approx 24.3$. 
The probability of obtaining a power
this high in a single trial from the expected $\chi^2$ noise distribution (2 dof) is
$\approx 5.29 \times 10^{-6}$. Multiplying this with the number of trials ($N_{\rm trial}$) 
would give the significance of this peak. 
The Nyquist frequency = 2048 Hz of our power spectrum, and five observed bursts from XB 1254--690
give $N_{\rm trial} = 10240$
for 1 Hz frequency resolution. This implies that the oscillations (at $\sim 95$ Hz)
are detected with $\approx 95$\% confidence. 
Although, the calculation of oscillation significance separately for each burst 
(as the presence of oscillations depends on burst properties and accretion history;
Galloway et al. 2006) would imply a detection from the 1996 burst with 98.9\% confidence
($N_{\rm trial} = 2048$), the more conservative value (95\%) should be acceptable, because of
the lack of our complete understanding of burst oscillations.

We have also fitted the phase-folded lightcurve of 1 s of data (the same data used to calculate
the power spectrum of Fig. 3) with a combined model of a sinusoid and a constant ($\chi^2/{\rm dof} = 
3.2/13$), and found that the oscillation rms amplitude is $0.31\pm0.07$. These values of fractional
rms amplitude are consistent with that expected for a hot spot on a spinning neutron star surface
(Miller \& Lamb 1998). These values are also consistent with the rms amplitude value (= 0.27) 
obtained from the formula $(P_{\rm n}/I)^{1/2} (I/(I-B))$ (Muno, {\"O}zel, Chakrabarty 2003).
Here $P_{\rm n}$ is the power at the nth bin of the Fourier
spectrum, $I$ is the total number of counts in the profile, and $B$ is the estimated
number of background counts in the profile. We have not found any significant burst
oscillation frequency evolution, as were seen from some other bursting sources
(e.g., Strohmayer et al. 1998; Bhattacharyya \& Strohmayer 2006c; Bhattacharyya et al. 2006a).

We have searched for kHz QPOs in the whole data set, and found a tentative indication of
$\approx$1000 Hz QPOs in the ObsID 20066-01-01-04. 
The significance of these plausible kHz QPOs is $\approx 2.66 \sigma$.
The high centroid frequency, the low $Q$-value $(\sim 2.44)$, and 
the inferred fractional rms amplitude ($\approx 0.12$) are consistent with those of
upper frequency kHz QPOs observed from other sources (see, for example, 
Barret, Olive, Miller, 2005). This plausible timing feature appeared in the relatively
lower portion (that is lower soft colour and lower hard colour) of the 
banana branch. This is consistent with what has been seen in other atoll
sources, because kHz QPOs are normally found in the ``lower left banana" portion
of the CD (van der Klis 2004).
If confirmed, this timing feature will be the first kHz QPOs observed from this source.
However, more significant detection of this feature is essential, as 
this plausible kHz QPOs appeared only in a small ($\sim 400$ s) data set.

\section{Discussion}

In this paper, we have estimated the luminosity range (in the unit of Eddington luminosity)
of XB 1254--690, calculated the colour-colour diagram, hardness-intensity diagram and 
persistent emission power spectra
of this source, and established that this source is an atoll source. 
This is an important first step to identify various states of this source.
As we have mentioned in \S~1, XB 1254--690 is a dipping LMXB, and hence can be
particularly useful to understand the properties of the upper layers of accretion discs, and the
photoionized plasma above them in LMXBs. Moreover, spectral lines are normally observed from 
the dippers, and X--ray absorption lines were actually detected from XB 1254--690 (Boirin et al. 2004).
Therefore, this source can be very promising for understanding LMXBs, if its
timing and spectral features can be correlated to its various states. In this paper,
we have already associated some low-frequency broad timing features with the LB and
UB states of XB 1254--690. These, as well as the weak indication of a kHz QPO (see \S~2),
will encourage more observations of this source. Moreover, dippers can exhibit
$\sim 1$ Hz QPOs, and to the best of our knowledge, such QPOs have been detected from
four dippers so far (Jonker, van der Klis, Wijnands 1999; Homan et al. 1999; Jonker et al. 2000;
Bhattacharyya et al. 2006c). However, these QPOs are observed at the low intensity states,
which might explain why they were never observed from XB 1254--690, as according to our analysis,
this source was
always in the high intensity banana state during {\it RXTE} observations. This may motivate
{\it RXTE} observations of XB 1254--690 at low intensities.

We have found a suggestive evidence of burst oscillations from XB 1254--690,
and if confirmed (by the detection of more bursts), 
these will provide the neutron star spin frequency. The plausible
oscillations were observed from only one burst out of the five
observed from this source, although the other properties of all these bursts seem similar.
This is typical of other burst oscillation sources, and 
may be understood from the the recent work of Spitkovsky et al.
(2002). According to these authors, the low-latitude 
ignition of bursts is much more likely, and oscillations do not occur for such ignitions.
This supports the calculation of oscillation significance separately for each burst,
although a better understanding of burst oscillations is required to strongly justify such
calculation (see \S~2). Finally, if the $95$ Hz burst oscillations
from XB 1254--690 are confirmed, the neutron star with low spin frequency (inferred from
the oscillations) will be ideal to search for surface atomic spectral absorption lines
(see Cottam, Paerels, M\'endez 2002; Bhattacharyya, Miller, Lamb 2006b), which may
have sufficient depths for detection.

\section*{Acknowledgments}

The author thanks Tod E. Strohmayer for detailed discussion, and 
an anonymous referee for helpful suggestions. 
This work was supported in part by NASA Guest
Investigator grants.

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\newpage
%\citet{b15}.
\begin{table*}
 \centering
 \begin{minipage}{140mm}
  \caption{Channel and energy boundaries of the soft colour, hard colour, and
intensity used in Figure 1.
}
\begin{tabular}{@{}lcccccc@{}}
  \hline\\
Year & Channels\footnote{The channel numbers refer to the absolute
PCA channels (0--255).} & keV & Channels$^a$ & keV & Channels$^a$ & keV \\
 & (Soft colour) & (Soft colour) & (Hard colour) & (Hard colour) & (Intensity) & (Intensity) \\
 \hline\\
1996 & 10--13/6--9  & 3.71--5.15/2.29--3.71 & 24--49/14--23 & 8.74--18.23/5.15--8.74 & 6--49 &
2.29--18.23 \\
1997 & 10--13/6--9  & 3.68--5.11/2.26--3.68 & 24--49/14--23 & 8.70--18.18/5.11--8.70 & 6--49 &
2.26--18.18 \\
2001 (May) & 9--12/6--8 & 3.58--5.28/2.30--3.58 & 21--42/13--20 & 8.69--18.16/5.28--8.69 & 6--42 &
2.30--18.16 \\
2001 (Dec) & 9--12/6--8 & 3.55--5.25/2.29--3.55 & 21--42/13--20 & 8.65--18.09/5.25--8.65 & 6--42 &
2.29--18.09 \\
2004 & 9--12/6--8 & 3.45--5.12/2.21--3.45 & 21--43/13--20 & 8.46--18.15/5.12--8.46 & 6--43 &
2.21--18.15 \\
\hline\\
\end{tabular}
\end{minipage}
\end{table*}

\clearpage
%\citet{b15}.
\begin{table*}
 \centering
 \begin{minipage}{140mm}
  \caption{Best fit parameters
%\footnote{Power spectra are fitted either by constant+Lorentzian, or by constant+powerlaw in the energy range $\sim 2.6-30$ keV.} 
(with $1 \sigma$ error) for the low frequency (up to $\sim 100$ Hz) {\it RXTE} power spectra from XB 1254--690.}
\begin{tabular}{@{}ccccccc@{}}
  \hline
No.\footnote{1: ObsID 60044-01-01-01 (lower intensity), 2: ObsID 60044-01-01-01 (higher
intensity), 3: ObsID 90036-01-01-02 (low intensity), and 4: ObsID 90036-01-01-03 (high
intensity). Power spectra are fitted either by constant+Lorentzian, or by constant+powerlaw in the
energy range $\sim 2.6-30$ keV.} 
& PLN $\nu$\footnote{Index of power law noise ($\propto f^{\nu}$; $f$ is frequency).} &
PLN rms\footnote{RMS of power law; lower limit of integration is 0.004 Hz.} & L$_{f_{\rm
0}}$\footnote{Centroid frequency of Lorentzian ($\propto \lambda/[(f-f_{\rm 0})^2+(\lambda/2)^2]$).}
& L$_{\lambda}$\footnote{Full width at half maximum (FWHM) of Lorentzian.} & 
L$_{\rm rms}$\footnote{RMS of Lorentzian.} & $\chi^2/{\rm dof}$ \\
 & & (\%) & (Hz) & (Hz) & (\%) &  \\
 \hline
1 & $-1.17\pm0.08$ & $3.4\pm0.6$ & -- & -- & -- & $65.88/80$ \\
2 & $-0.92\pm0.06$ & $4.5\pm0.5$ & -- & -- & -- & $82.34/80$ \\
3 & -- & -- & $0.011\pm0.004$ & $0.018\pm0.007$ & $1.8\pm0.3$ & $22.67/18$\\
4 & $-1.44\pm0.13$ & $2.8\pm1.0$ & -- & -- & -- & $44.31/56$\\
\hline
\end{tabular}
\end{minipage}
\end{table*}

\input psbox.tex

\newpage
\begin{figure*}
\vspace{2.0 cm}
\hspace{-4.6 cm}
{\mbox{\psboxto(19cm;22cm){f1.eps}}}
\vspace{-8.0 cm}
\caption{Colour-colour diagram (left panel) and hardness-intensity diagram (right panel)
of XB 1254--690 using {\it RXTE} PCA data of the years 
1996 (proposal number: 10068; {\it square} signs), 1997 (proposal number: 20066; {\it cross} signs),
2001 (proposal number: 60044; {\it plus} signs), and 2004 (proposal number: 90036;
{\it diamond} signs). The definitions of the colours and the energy range of
the intensity are given in Table 1. Here we use only the top Xenon layers of the PCUs
0, 2 and 3, and exclude the flaring and dipping data. Each point is for 128 s of data.
Typical $1 \sigma$ error bars for soft and hard colours are shown in the left panel.
The ranges of soft colour, hard colour and intensity strongly indicate that XB 1254--690
is an atoll source.
}
\end{figure*}

\newpage
\begin{figure*}
%\hspace{1.6 cm}
{\mbox{\psboxto(12cm;16cm){f2.eps}}}
%\vspace{1 cm}
\caption{Low frequency power spectra (for the energy range $\sim 2.6-30$ keV) of XB 1254--690
using {\it RXTE} PCA data of 2004. The upper and lower panels are for the power spectrum numbers
3 (low intensity) and 4 (high intensity) of Table 2. Each panel shows the data points and the 
best fit model (solid line). The data of the upper panel are fitted well with `constant+Lorentzian',
while the best fit model for the lower panel data is `constant+powerlaw'. The `constant' 
describes the Poisson noise level, the `Lorentzian' indicates a broad hump or a band-limited
noise (BLN), and the `powerlaw' describes the very low frequency noise
(VLFN). These indicate that XB 1254--690 was in banana state during these observations.
The horizontal lines around the data points give the frequency bin, and the corresponding 
vertical lines give the $1 \sigma$ errors of powers.
}
\end{figure*}

\newpage
\begin{figure*}
%\hspace{1.6 cm}
{\mbox{\psboxto(15cm;18cm){f3.eps}}}
%\vspace{1 cm}
\caption{A thermonuclear X--ray burst from XB 1254--690 (1996 data). The main
panel shows the PCA count rate profile and the power contours (of the plausible burst oscillations)
using the dynamic power spectra (for 1.0 s duration at 0.1 s intervals; Strohmayer
\& Markwardt 1999). Contours at power levels of 19, 21, 23, 25, 27, 28.8 are given.
The inset panel shows a power spectrum of 1 s interval (the first such interval
after the burst count rate starts rising sharply) 
with 1 Hz frequency resolution. The peak near 95 Hz 
shows the plausible signal power.
}
\end{figure*}

\label{lastpage}

\end{document}

psbox.tex
%
%       %%%%%%%    %%%%%        %%%%%%    %%%%%   %     %
%       %      %  %             %     %  %     %   %   %
%       %      %  %             %     %  %     %    % %
%       %%%%%%%    %%%%%        %%%%%%   %     %     %
%       %               %       %     %  %     %    % %
%       %               %       %     %  %     %   %   %
%       %         %%%%%%        %%%%%%    %%%%%   %     %
%
%       By Jean Orloff
%
% WHAT IS IT:
% psbox is a set of machine-independent TeX macros to
% 1) allow (Encapsulated) PostScript figure inclusion in all versions
%    of TeX (Plain, LaTeX) on all machines using a PostScript printer
% 2) facilitate the communication (e-mail, ftp, ...) of all the files
%    (text, macros, figs) needed to reproduce a TeX document by grouping
%    them together into a single, TeXable file.
%
% History:
%  1.34  \readfilename=final fix for all filename scans; try \psforptips
%  1.33: corrects \psnewinput for LaTeX (still fails if fname=a{b}c)
%  1.32: corrects \psfordvialw and adds .TEX to PSBOXALL(!)
%  1.31: adds \psfordvialw(?)
%  1.30: adds \splitfile & \joinfiles for multi-file management
%  1.24: fix error handling & add \psonlyboxes
%  1.22: makes \drawingBox \global for use in Phyzzx
%  1.21: accepts %%BoundingBox: (atend)
%  1.20: tries to add \psfordvitps for the TeXPS package.
%  1.10: adds \psforoztex, error handling...
%2345678 1 2345678 2 2345678 3 2345678 4 2345678 5 2345678 6 2345678 7 23456789
%
% Checking version no to avoid multiple loadings
\def\temp{1.34}%
\let\tempp=\relax
\expandafter\ifx\csname psboxversion\endcsname\relax
  \message{PSBOX(\temp) loading}%
\else
    \ifdim\temp cm>\psboxversion cm
      \message{PSBOX(\temp) loading}%
    \else
      \message{PSBOX(\psboxversion) is already loaded: I won't load
        PSBOX(\temp)!}%
      \let\temp=\psboxversion
      \let\tempp=\endinput
    \fi
\fi
\tempp
\let\psboxversion=\temp
\catcode`\@=11
% Every macro likes a little privacy...
%
%Trying to tame the variety of \special commands for Postscript: the
%  universal internal command \PSspeci@l##1##2 takes ##1 to be the
%  filename and ##2 to be the integer scale factor*1000 (as for usual
%   TeX \scale commands)
%
\def\psfortextures{%     For TeXtures on the Macintosh
%-----------------
\def\PSspeci@l##1##2{%
\special{illustration ##1\space scaled ##2}%
}}%
\def\psfordvitops{%      For the DVItoPS converter on IBM mainframes
%----------------
\def\PSspeci@l##1##2{%
\special{dvitops: import ##1\space \the\drawingwd \the\drawinght}%
}}%
\def\psfordvips{%      For DVIPS converter on VAX, UNIX and PC's
%--------------
\def\PSspeci@l##1##2{%
%    \special{/@scaleunit 1000 def}% never read dox without trying!
\d@my=0.1bp \d@mx=\drawingwd \divide\d@mx by\d@my% BUG! for large \drawingwd
\special{PSfile=##1\space llx=\psllx\space lly=\pslly\space%
urx=\psurx\space ury=\psury\space rwi=\number\d@mx
}}}%
\def\psforoztex{%        For the OzTeX shareware on the Macintosh
%--------------
\def\PSspeci@l##1##2{%
\special{##1 \space
      ##2 1000 div dup scale
      \number-\psllx\space \number-\pslly\space translate
}}}%
\def\psfordvitps{%       From the UNIX TeXPS package, vers.>3.12
%---------------
% Convert a dimension into the number \psn@sp (in scaled points)
\def\psdimt@n@sp##1{\d@mx=##1\relax\edef\psn@sp{\number\d@mx}}
\def\PSspeci@l##1##2{%
% psfig.psr contains the def of "startTexFig": if you can locate it
% and include the correct pathname, it should work
\special{dvitps: Include0 "psfig.psr"}% contains def of "startTexFig"
\psdimt@n@sp{\drawingwd}
\special{dvitps: Literal "\psn@sp\space"}
\psdimt@n@sp{\drawinght}
\special{dvitps: Literal "\psn@sp\space"}
\psdimt@n@sp{\psllx bp}
\special{dvitps: Literal "\psn@sp\space"}
\psdimt@n@sp{\pslly bp}
\special{dvitps: Literal "\psn@sp\space"}
\psdimt@n@sp{\psurx bp}
\special{dvitps: Literal "\psn@sp\space"}
\psdimt@n@sp{\psury bp}
\special{dvitps: Literal "\psn@sp\space startTexFig\space"}
\special{dvitps: Include1 "##1"}
\special{dvitps: Literal "endTexFig\space"}
}}%
\def\psfordvialw{%   Try for dvialw, a UNIX public domain
%---------------
\def\PSspeci@l##1##2{
\special{language "PostScript",
position = "bottom left",
literal "  \psllx\space \pslly\space translate
  ##2 1000 div dup scale
  -\psllx\space -\pslly\space translate",
include "##1"}
}}%
\def\psforptips{%   For MS-DOS; LUOMA@brandeis.bitnet
%---------------
\def\PSspeci@l##1##2{{
\d@mx=\psurx bp
\advance \d@mx by -\psllx bp
\divide \d@mx by 1000\multiply\d@mx by \xscale
\incm{\d@mx}
\let\tmpx\dimincm
\d@my=\psury bp
\advance \d@my by -\pslly bp
\divide \d@my by 1000\multiply\d@my by \xscale
\incm{\d@my}
\let\tmpy\dimincm
\d@mx=-\psllx bp
\divide \d@mx by 1000\multiply\d@mx by \xscale
\d@my=-\pslly bp
\divide \d@my by 1000\multiply\d@my by \xscale
\at(\d@mx;\d@my){\special{ps:##1 x=\tmpx, y=\tmpy}}
}}}%
\def\psonlyboxes{%     Draft-like behaviour if none of the others works
%---------------
\def\PSspeci@l##1##2{%
\at(0cm;0cm){\boxit{\vbox to\drawinght
  {\vss\hbox to\drawingwd{\at(0cm;0cm){\hbox{({\tt##1})}}\hss}}}}
}}%
\def\psloc@lerr#1{%
\let\savedPSspeci@l=\PSspeci@l%
\def\PSspeci@l##1##2{%
\at(0cm;0cm){\boxit{\vbox to\drawinght
  {\vss\hbox to\drawingwd{\at(0cm;0cm){\hbox{({\tt##1}) #1}}\hss}}}}
\let\PSspeci@l=\savedPSspeci@l% restore normal output for other figs!
}}%
%\def\psfor...  add your own!
%
% Some common defs
%
\newread\pst@mpin
\newdimen\drawinght\newdimen\drawingwd
\newdimen\psxoffset\newdimen\psyoffset
\newbox\drawingBox
\newcount\xscale \newcount\yscale \newdimen\pscm\pscm=1cm
\newdimen\d@mx \newdimen\d@my
\newdimen\pswdincr \newdimen\pshtincr
\let\ps@nnotation=\relax
{\catcode`\|=0 |catcode`|\=12 |catcode`|%=12 |catcode`~=12
|catcode`#=12 |catcode`*=14
|xdef|backslashother{\}*
|xdef|percentother{%}*
|xdef|tildeother{~}*
|xdef|sharpother{#}*
}%
% useful to display special chars in \tt; fails for \,#,%
\def\R@moveMeaningHeader#1:->{}%
\def\uncatcode#1{%
\edef#1{\expandafter\R@moveMeaningHeader\meaning#1}}%
%
\def\execute#1{#1}% NOT stupid: cs in #1 are then identified BEFORE execution
\def\psm@keother#1{\catcode`#112\relax}% borrowed from latex
\def\executeinspecs#1{%
\execute{\begingroup\let\do\psm@keother\dospecials\catcode`\^^M=9#1\endgroup}}%
\def\@mpty{}%
% \if\matchin#1#2<=> \iftrue if #1 contains #2, <=>\iffalse otherwise:
% \if\matchexpin: idem, but #1 & #2 are first fully expanded (no \if
% inside!)
% \tmpa & \tmpb contain what's before and after the occurence of #2
\def\matchexpin#1#2{
  \fi%
%\message{(#1>#2)}
  \edef\tmpb{{#2}}%
  \expandafter\makem@tchtmp\tmpb%
  \edef\tmpa{#1}\edef\tmpb{#2}%
  \expandafter\expandafter\expandafter\m@tchtmp\expandafter\tmpa\tmpb\endm@tch%
  \if\match%
}%
\def\matchin#1#2{%
  \fi%
  \makem@tchtmp{#2}%
  \m@tchtmp#1#2\endm@tch%
  \if\match%
}%
\def\makem@tchtmp#1{\def\m@tchtmp##1#1##2\endm@tch{%
  \def\tmpa{##1}\def\tmpb{##2}\let\m@tchtmp=\relax%
  \ifx\tmpb\@mpty\def\match{YN}%
  \else\def\match{YY}\fi%
}}%
% converts any dimen in cm, with 1E-4 cm precision
\def\incm#1{{\psxoffset=1cm\d@my=#1
 \d@mx=\d@my
  \divide\d@mx by \psxoffset
  \xdef\dimincm{\number\d@mx.}
  \advance\d@my by -\number\d@mx cm
  \multiply\d@my by 100
 \d@mx=\d@my
  \divide\d@mx by \psxoffset
  \edef\dimincm{\dimincm\number\d@mx}
  \advance\d@my by -\number\d@mx cm
  \multiply\d@my by 100
 \d@mx=\d@my
  \divide\d@mx by \psxoffset
  \xdef\dimincm{\dimincm\number\d@mx}
}}%
%
%  \ReadPSize{PSfilename} reads the dimensions of a PostScript drawing
%      and stores it in \drawinght(wd)
\newif\ifNotB@undingBox
\newhelp\PShelp{Proceed: you'll have a 5cm square blank box instead of
your graphics (Jean Orloff).}%
\def\s@tsize#1 #2 #3 #4\@ndsize{
  \def\psllx{#1}\def\pslly{#2}%
  \def\psurx{#3}\def\psury{#4}%  needed by a crazyness of dvips!
  \ifx\psurx\@mpty\NotB@undingBoxtrue% this is not a valid one!
  \else
    \drawinght=#4bp\advance\drawinght by-#2bp
    \drawingwd=#3bp\advance\drawingwd by-#1bp
%  !Units related by crazy factors as bp/pt=72.27/72 should be BANNED!
  \fi
  }%
\def\sc@nBBline#1:#2\@ndBBline{\edef\p@rameter{#1}\edef\v@lue{#2}}%
\def\g@bblefirstblank#1#2:{\ifx#1 \else#1\fi#2}%
{\catcode`\%=12
\xdef\B@undingBox{%%BoundingBox}}%
%% is not a true comment in PostScript, even if % is!
\def\ReadPSize#1{
 \readfilename#1\relax
 \let\PSfilename=\lastreadfilename
 \openin\pst@mpin=#1\relax
 \ifeof\pst@mpin \errhelp=\PShelp
   \errmessage{I haven't found your postscript file (\PSfilename)}%
   \psloc@lerr{was not found}%
   \s@tsize 0 0 142 142\@ndsize
   \closein\pst@mpin
 \else
% each entry in \GlobalInputList should be unique
   \if\matchexpin{\GlobalInputList}{, \lastreadfilename}%
   \else\xdef\GlobalInputList{\GlobalInputList, \lastreadfilename}%
     \immediate\write\psbj@inaux{\lastreadfilename,}%
   \fi%
   \loop
     \executeinspecs{\catcode`\ =10\global\read\pst@mpin to\n@xtline}%
     \ifeof\pst@mpin
       \errhelp=\PShelp
       \errmessage{(\PSfilename) is not an Encapsulated PostScript File:
           I could not find any \B@undingBox: line.}%
       \edef\v@lue{0 0 142 142:}%
       \psloc@lerr{is not an EPSFile}%
       \NotB@undingBoxfalse
     \else
       \expandafter\sc@nBBline\n@xtline:\@ndBBline
       \ifx\p@rameter\B@undingBox\NotB@undingBoxfalse
         \edef\t@mp{%
           \expandafter\g@bblefirstblank\v@lue\space\space\space}%
         \expandafter\s@tsize\t@mp\@ndsize
       \else\NotB@undingBoxtrue
       \fi
     \fi
   \ifNotB@undingBox\repeat
   \closein\pst@mpin
 \fi
\message{#1}%
}%
%
% \psboxto(xdim;ydim){psfilename}: you specify the dimensions and
%    TeX uniformly scales to fit the largest one. If xdim=0pt, the
%    scale is fully determined by ydim and vice versa.
%    Notice: psboxes are a real vboxes; couldn't take hbox otherwise all
%    indentation and all cr's would be interpreted as spaces (hugh!).
%
\def\psboxto(#1;#2)#3{\vbox{
   \ReadPSize{#3}%
   \divide\drawingwd by 1000
   \divide\drawinght by 1000
   \d@mx=#1
   \ifdim\d@mx=0pt\xscale=1000
         \else \xscale=\d@mx \divide \xscale by \drawingwd\fi
   \d@my=#2
   \ifdim\d@my=0pt\yscale=1000
         \else \yscale=\d@my \divide \yscale by \drawinght\fi
   \ifnum\yscale=1000
         \else\ifnum\xscale=1000\xscale=\yscale
                    \else\ifnum\yscale<\xscale\xscale=\yscale\fi
              \fi
   \fi
   \divide\pswdincr by 1000 \multiply\pswdincr by \xscale
   \divide\pshtincr by 1000 \multiply\pshtincr by \xscale
   \divide\psxoffset by1000 \multiply\psxoffset by\xscale
   \divide\psyoffset by1000 \multiply\psyoffset by\xscale
   \global\divide\pscm by 1000
   \global\multiply\pscm by\xscale
   \multiply\drawingwd by\xscale \multiply\drawinght by\xscale
   \ifdim\d@mx=0pt\d@mx=\drawingwd\fi
   \ifdim\d@my=0pt\d@my=\drawinght\fi
   \message{scaled \the\xscale}%
 \hbox to\d@mx{\hss\vbox to\d@my{\vss
   \global\setbox\drawingBox=\hbox to 0pt{\kern\psxoffset\vbox to 0pt{
      \kern-\psyoffset
      \PSspeci@l{\PSfilename}{\the\xscale}%
      \vss}\hss\ps@nnotation}%
   \advance\pswdincr by \drawingwd
   \advance\pshtincr by \drawinght
   \global\wd\drawingBox=\the\pswdincr
   \global\ht\drawingBox=\the\pshtincr
   \baselineskip=0pt
   \copy\drawingBox
 \vss}\hss}%
  \global\psxoffset=0pt
  \global\psyoffset=0pt
  \global\pswdincr=0pt
  \global\pshtincr=0pt % These are local to one figure
  \global\pscm=1cm %should not be necessary
  \global\drawingwd=\drawingwd
  \global\drawinght=\drawinght
}}%
%
% \psboxscaled{scalefactor*1000}{PSfilename} allows to bypass the
%   rounding errors of TeX integer divisions for situations where the
%   TeX box should fit the original BoundingBox with a precision better
%   than 1/1000.
%
\def\psboxscaled#1#2{\vbox{
  \ReadPSize{#2}%
  \xscale=#1
  \message{scaled \the\xscale}%
  \advance\drawingwd by\pswdincr\advance\drawinght by\pshtincr
  \divide\pswdincr by 1000 \multiply\pswdincr by \xscale
  \divide\pshtincr by 1000 \multiply\pshtincr by \xscale
  \divide\psxoffset by1000 \multiply\psxoffset by\xscale
  \divide\psyoffset by1000 \multiply\psyoffset by\xscale
  \divide\drawingwd by1000 \multiply\drawingwd by\xscale
  \divide\drawinght by1000 \multiply\drawinght by\xscale
  \global\divide\pscm by 1000
  \global\multiply\pscm by\xscale
  \global\setbox\drawingBox=\hbox to 0pt{\kern\psxoffset\vbox to 0pt{
     \kern-\psyoffset
     \PSspeci@l{\PSfilename}{\the\xscale}%
     \vss}\hss\ps@nnotation}%
  \advance\pswdincr by \drawingwd
  \advance\pshtincr by \drawinght
  \global\wd\drawingBox=\the\pswdincr
  \global\ht\drawingBox=\the\pshtincr
  \baselineskip=0pt
  \copy\drawingBox
  \global\psxoffset=0pt
  \global\psyoffset=0pt
  \global\pswdincr=0pt
  \global\pshtincr=0pt % These are local to one figure
  \global\pscm=1cm
  \global\drawingwd=\drawingwd
  \global\drawinght=\drawinght
}}%
%
%  \psbox{PSfilename} makes a TeX box having the minimal size to
%      enclose the picture
\def\psbox#1{\psboxscaled{1000}{#1}}%
%------------------------------------------------------
%  \joinfiles file1, file2, ...n \into joinedfilename .
%     makes one file out of many
%  \splitfile joinedfilename
%     the opposite
\newif\ifn@teof\n@teoftrue
\newif\ifc@ntrolline
\newif\ifmatch
\newread\j@insplitin
\newwrite\j@insplitout
\newwrite\psbj@inaux
\immediate\openout\psbj@inaux=psbjoin.aux
\immediate\write\psbj@inaux{\string\joinfiles}%
\immediate\write\psbj@inaux{\jobname,}%
%
% INPUT REDEFINITION
%
% works if #1 is a single character
\def\toother#1{\ifcat\relax#1\else\expandafter%
  \toother@ux\meaning#1\endtoother@ux\fi}%
\def\toother@ux#1 #2#3\endtoother@ux{\def\tmp{#3}%
  \ifx\tmp\@mpty\def\tmp{#2}\let\next=\relax%
  \else\def\next{\toother@ux#2#3\endtoother@ux}\fi%
\next}%
%
% \readfilename defs:
%
\let\readfilenamehook=\relax
\def\re@d{\expandafter\re@daux}% spares typing 10 \expandafter's...
\def\re@daux{\futurelet\nextchar\stopre@dtest}%
\def\re@dnext{\xdef\lastreadfilename{\lastreadfilename\nextchar}%
  \afterassignment\re@d\let\nextchar}%
\def\stopre@d{\egroup\readfilenamehook}%
\def\stopre@dtest{%
  \ifcat\nextchar\relax\let\nextread\stopre@d
  \else
    \ifcat\nextchar\space\def\nextread{%
      \afterassignment\stopre@d\chardef\nextchar=`}%
    \else\let\nextread=\re@dnext
      \toother\nextchar
      \edef\nextchar{\tmp}%
    \fi
  \fi\nextread}%
\def\readfilename{\vbox\bgroup%
  \let\\=\backslashother \let\%=\percentother \let\~=\tildeother
  \let\#=\sharpother \xdef\lastreadfilename{}%
  \re@d}%
%
% redefines \input using \readfilename
%
\xdef\GlobalInputList{\jobname}%
\def\psnewinput{%
  \def\readfilenamehook{% each entry in \GlobalInputList should be unique
    \if\matchexpin{\GlobalInputList}{, \lastreadfilename}%
    \else\xdef\GlobalInputList{\GlobalInputList, \lastreadfilename}%
      \immediate\write\psbj@inaux{\lastreadfilename,}%
    \fi%
    \ps@ldinput\lastreadfilename\relax%
    \let\readfilenamehook=\relax%
  }\readfilename%
}%
\expandafter\ifx\csname @@input\endcsname\relax    % then Plain
  \immediate\let\ps@ldinput=\input\def\input{\psnewinput}%
\else
  \immediate\let\ps@ldinput=\@@input
  \def\@@input{\psnewinput}%
\fi%
%
\def\nowarnopenout{%
 \def\warnopenout##1##2{%
   \readfilename##2\relax
   \message{\lastreadfilename}%
   \immediate\openout##1=\lastreadfilename\relax}}%
\def\warnopenout#1#2{%
 \readfilename#2\relax
 \def\t@mp{TrashMe,psbjoin.aux,psbjoint.tex,}\uncatcode\t@mp
 \if\matchexpin{\t@mp}{\lastreadfilename,}%
 \else
   \immediate\openin\pst@mpin=\lastreadfilename\relax
   \ifeof\pst@mpin
     \else
     \errhelp{If the content of this file is so precious to you, abort (ie
press x or e) and rename it before retrying.}%
     \errmessage{I'm just about to replace your file named \lastreadfilename}%
   \fi
   \immediate\closein\pst@mpin
 \fi
 \message{\lastreadfilename}%
 \immediate\openout#1=\lastreadfilename\relax}%
% % will have an unusual catcode below; use * instead
%\vbox
{\catcode`\%=12\catcode`\*=14
\gdef\splitfile#1{*
 \readfilename#1\relax
 \immediate\openin\j@insplitin=\lastreadfilename\relax
 \ifeof\j@insplitin
   \message{! I couldn't find and split \lastreadfilename!}*
 \else
   \immediate\openout\j@insplitout=TrashMe
   \message{< Splitting \lastreadfilename\space into}*
   \loop
     \ifeof\j@insplitin
       \immediate\closein\j@insplitin\n@teoffalse
     \else
       \n@teoftrue
       \executeinspecs{\global\read\j@insplitin to\spl@tinline\expandafter
         \ch@ckbeginnewfile\spl@tinline%Beginning-Of-File-Named:%\endcheck}*
       \ifc@ntrolline
       \else
         \toks0=\expandafter{\spl@tinline}*
         \immediate\write\j@insplitout{\the\toks0}*
       \fi
     \fi
   \ifn@teof\repeat
   \immediate\closeout\j@insplitout
 \fi\message{>}*
}*
\gdef\ch@ckbeginnewfile#1%Beginning-Of-File-Named:#2%#3\endcheck{*
 \def\t@mp{#1}*
 \ifx\@mpty\t@mp
   \def\t@mp{#3}*
   \ifx\@mpty\t@mp
     \global\c@ntrollinefalse
   \else
     \immediate\closeout\j@insplitout
     \warnopenout\j@insplitout{#2}*
     \global\c@ntrollinetrue
   \fi
 \else
   \global\c@ntrollinefalse
 \fi}*
\gdef\joinfiles#1\into#2{*
 \message{< Joining following files into}*
 \warnopenout\j@insplitout{#2}*
 \message{:}*
 {*
 \edef\w@##1{\immediate\write\j@insplitout{##1}}*
\w@{% This collection of files was produced with CERN psbox package}*
\w@{% To decompose and tex it:}*
\w@{%-save this with a filename CONTAINING ONLY LETTERS and a .TEX}*
\w@{% extension (say, JOINTFIL.TEX), in some uncrowded directory;}*
\w@{%-make sure you can \string\input\space psbox.tex (version>=1.3);}*
\w@{%  (else ftp cs.nyu.edu(=128.122.140.24):pub/TeX/psbox/, then get}*
\w@{%  and tex the file psboxall.tex; more info in psbREAD.ME)}*
\w@{%-tex JOINTFIL.TEX using Plain, or LaTeX, or whatever is needed by}*
\w@{%  the first file in the joining (after splitting JOINTFIL.TEX into}*
\w@{%  it's constituents, TeX will try to process it as it stands).}*
\w@{\string\input\space psbox.tex}*
\w@{\string\splitfile{\string\jobname}}*
\w@{\string\let\string\autojoin=\string\relax}*
}*
 \expandafter\tre@tfilelist#1, \endtre@t
 \immediate\closeout\j@insplitout
 \message{>}*
}*
\gdef\tre@tfilelist#1, #2\endtre@t{*
 \readfilename#1\relax
 \ifx\@mpty\lastreadfilename
 \else
   \immediate\openin\j@insplitin=\lastreadfilename\relax
   \ifeof\j@insplitin
     \errmessage{I couldn't find file \lastreadfilename}*
   \else
     \message{\lastreadfilename}*
     \immediate\write\j@insplitout{%Beginning-Of-File-Named:\lastreadfilename}*
     \executeinspecs{\global\read\j@insplitin to\oldj@ininline}*
     \loop
       \ifeof\j@insplitin\immediate\closein\j@insplitin\n@teoffalse
       \else\n@teoftrue
         \executeinspecs{\global\read\j@insplitin to\j@ininline}*
         \toks0=\expandafter{\oldj@ininline}*
         \let\oldj@ininline=\j@ininline
         \immediate\write\j@insplitout{\the\toks0}*
       \fi
     \ifn@teof
     \repeat
   \immediate\closein\j@insplitin
   \fi
   \tre@tfilelist#2, \endtre@t
 \fi}*
}%
% To be put at the end of a file, for making a tar-like file containing
%   everything it used.
\def\autojoin{%
 \immediate\write\psbj@inaux{\string\into{psbjoint.tex}}%
 \immediate\closeout\psbj@inaux
 \expandafter\joinfiles\GlobalInputList\into{psbjoint.tex}%
}%
%----------------------------------------------------------------
%  Annotations & Captions etc...
%
%
% \centinsert{anybox} is just a centered \midinsert, but is included as
%    people barely use the original inserts from TeX.
%
\def\centinsert#1{\midinsert\line{\hss#1\hss}\endinsert}%
\def\psannotate#1#2{\vbox{%
  \def\ps@nnotation{#2\global\let\ps@nnotation=\relax}#1}}%
\def\pscaption#1#2{\vbox{%
   \setbox\drawingBox=#1
   \copy\drawingBox
   \vskip\baselineskip
   \vbox{\hsize=\wd\drawingBox\setbox0=\hbox{#2}%
     \ifdim\wd0>\hsize
       \noindent\unhbox0\tolerance=5000
    \else\centerline{\box0}%
    \fi
}}}%
% for compatibility with older versions, but \psfig is a bad name!
%\def\psfig#1#2#3{\pscaption{\psannotate{#1}{#2}}{#3}}
%\def\psfigurebox#1#2#3{\pscaption{\psannotate{\psbox{#1}}{#2}}{#3}}
%
% \at(#1;#2)#3 puts #3 at #1-higher and #2-right of the current
%    position without moving it (to be used in annotations).
\def\at(#1;#2)#3{\setbox0=\hbox{#3}\ht0=0pt\dp0=0pt
  \rlap{\kern#1\vbox to0pt{\kern-#2\box0\vss}}}%
%
% \gridfill(ht;wd) makes a 1cm*1cm grid of ht by wd whose lower-left
%   corner is the current point
\newdimen\gridht \newdimen\gridwd
\def\gridfill(#1;#2){%
  \setbox0=\hbox to 1\pscm
  {\vrule height1\pscm width.4pt\leaders\hrule\hfill}%
  \gridht=#1
  \divide\gridht by \ht0
  \multiply\gridht by \ht0
  \gridwd=#2
  \divide\gridwd by \wd0
  \multiply\gridwd by \wd0
  \advance \gridwd by \wd0
  \vbox to \gridht{\leaders\hbox to\gridwd{\leaders\box0\hfill}\vfill}}%
%
% Useful to measure where to put annotations
\def\fillinggrid{\at(0cm;0cm){\vbox{%
  \gridfill(\drawinght;\drawingwd)}}}%
%
% \textleftof\anybox: Sample text\endtext
%   inserts "Sample text" on the left of \anybox ie \vbox, \psbox.
%   \textrightof is the symmetric (not documented, too uggly)
% Welcome any suggestion about clean wraparound macros from
%   TeXhackers reading this
%
\def\textleftof#1:{%
  \setbox1=#1
  \setbox0=\vbox\bgroup
    \advance\hsize by -\wd1 \advance\hsize by -2em}%
\def\textrightof#1:{%
  \setbox0=#1
  \setbox1=\vbox\bgroup
    \advance\hsize by -\wd0 \advance\hsize by -2em}%
\def\endtext{%
  \egroup
  \hbox to \hsize{\valign{\vfil##\vfil\cr%
\box0\cr%
\noalign{\hss}\box1\cr}}}%
%
% \frameit{\thick}{\skip}{\anybox}
%    draws with thickness \thick a box around \anybox, leaving \skip of
%    blank around it. eg \frameit{0.5pt}{1pt}{\hbox{hello}}
% \boxit{\anybox} is a shortcut.
\def\frameit#1#2#3{\hbox{\vrule width#1\vbox{%
  \hrule height#1\vskip#2\hbox{\hskip#2\vbox{#3}\hskip#2}%
        \vskip#2\hrule height#1}\vrule width#1}}%
\def\boxit#1{\frameit{0.4pt}{0pt}{#1}}%
%
%
\catcode`\@=12 % cs containing @ are unreachable
%
% CUSTOMIZE YOUR DEFAULT DRIVER:
%    Uncomment the line corresponding to your TeX system:
%\psfortextures%     For TeXtures on the Macintosh
%\psforoztex   %     For OzTeX shareware on the Macintosh
%\psfordvitops %     For the DVItoPS converter for TeX on IBM mainframes
 \psfordvips   %     For DVIPS converter on VAX and UNIX
%\psfordvitps  %     For dvitps from TeXPS package under UNIX
%\psfordvialw  %     For dvialw, UNIX public domain
%\psonlyboxes  %     Blank Boxes (when all else fails).

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