Conversion to Python

A simple plot
Two plots: plotting data from a file and from arrays
Preferences and Histograms

Here we convert several CIAO 3 plots to the Python interface of CIAO 4. The examples use a text file, sample.txt, whose contents are

# x y dy
1   10    3
2.5 20    5
5   17    5
9   21  5.5
12  -5    3
20  25    7
40  80   11

The CIAO 4 examples assume that you have not set the CHIPS_SCRIPT_LANG environment variable set to slang, or changed the chips.shell preference setting in ~/.chips.rc from python. For further information see the Starting ChIPS thread.

A complete list of all the CIAO 3.4 ChIPS commands and their Python equivalents in CIAO 4 is also available.

A simple plot

This example illustrates how you convert several common CIAO 3.4 commands, including CURVE, LABEL, LINE, XLABEL, YLABEL, TITLE, and PRINT.

CIAO 3.4 output	CIAO 4.0 output

CIAO 3 command language

unix% chips

Welcome to ChIPS, version CIAO 3.4
Copyright (C) 1999-2003, Smithsonian Astrophysical Observatory

chips> curve "sample.txt" x 1 y 2
chips> sym square
chips> label 5 70 "Main sample (\beta<0.5)"
chips> line -100 -100 100 100
chips> line red
chips> line dash
chips> xlabel "r (kpc)"
chips> ylabel "\alpha / \alpha_0"
chips> title "Comparison plot 1"
chips> label size 1.2
chips> xlabel size 1.2
chips> ylabel size 1.2
chips> title size 1.2
chips> print postfile plot1.ps
chips> info

Drawing Area  #1  << CURRENT DRAWING AREA
(Location: 0.15 0.9 0.1 0.9) 
(Limits  : -0.95 41.95 -9.25 84.25) 
(Axes    :  fouraxes   color: defaultcolor  width: 1) 
        Curve #1  /data/chips/sample.txt
                 SYMBOL: defaultcolor  square 
                 CONNECTOR: noline  << CURRENT CURVE
        Label #1  "Main sample (\beta<0.5)" Location: (5, 70) Size: 1.2  << CURRENT LABEL
        Line  #1  Starting at (-100, -100) ending at (100, 100) Color: red   << CURRENT LINE

where bold text in the output from INFO is used to indicate text in reverse video.

CIAO 4 Python version

unix% chips
chips-1> add_curve("sample.txt[cols x,y]",["line.style","none"])
chips-2> set_curve(["symbol.style","square","symbol.fill",0])
chips-3> add_label(5,70,r"Main sample (\beta<0.5)")
chips-4> add_line (0,0,40,40,["extend","both","color","red","style","longdash"])
chips-5> set_plot_xlabel("r (kpc)")
chips-6> set_plot_ylabel(r"\alpha / \alpha_0")
chips-7> set_plot_title("Comparison plot 1")
chips-8> set_label(["size",18])
chips-9> set_axis(["label.size",18])
chips-10> set_plot(["title.size",18])
chips-11> print_window("plot1") 
chips-12> print info()
Window [win1]
  Frame [frm1]
    Plot [plot1]   (0.15,0.15)  .. (0.90,0.90)
      Border bottom [bx1]  top [bx2]  left [by1]  right [by2]
      X Axis [ax1]
      Y Axis [ay1]
      Curve [crv1]
    Label [lbl1]
    Line [line1]

chips-13> get_plot_xrange()
[-0.95000000000000018, 41.950000000000003]
chips-14> get_plot_yrange()
[-9.25, 84.25]
chips-15> print get_line()
color = red
depth = 100
extend = 3
id = None
stem = None
style = 5
thickness = 1.0

Two plots: plotting data from a file and from arrays

This example show how you convert the SPLIT and RELSIZE commands, as well as the curve() S-Lang function.

CIAO 3.4 output	CIAO 4.0 output

Note that the blue dotted line connecting the curve is not drawn to the point that has y < 0 in CIAO 4.0, due to the logarithmic scale used for the Y axis, whereas it was in CIAO 3.4 (or at least a line was drawn vertically down).

CIAO 3 command language

unix% chips

Welcome to ChIPS, version CIAO 3.4
Copyright (C) 1999-2003, Smithsonian Astrophysical Observatory

chips> curve "sample.txt" x 1 y 2 e 3
chips> log y
chips> limits y 6 auto
chips> sym magenta
chips> err red
chips> simpleline
chips> blue
chips> longdash
chips> split 2
chips> split gap 0.1
chips> relsize 2
chips> d 2
chips> x = [1:10:0.1];
chips> y = sin(x);
chips> () = curve(x,y);
chips> simpleline
chips> sym none
chips> magenta
chips> xlabel x_2
chips> ylabel y_2
chips> xlabel size 1.6
chips> ylabel size 1.6
chips> xlabel magenta
chips> ylabel magenta
chips> d 1
chips> xlabel \eta
chips> ylabel "rate (count s^{-1})"
chips> xlabel size 1.6
chips> ylabel size 1.6
chips> print postfile plot2.ps

CIAO 4 S-Lang version

unix% chips
chips-1> add_curve("sample.txt[cols x,y,dy]",["line.style","none"])
chips-2> log_scale(Y_AXIS)
chips-3> ci = ChipsCurve()
chips-4> ci.err.style = "cap"
chips-5> ci.err.color = "red"
chips-6> ci.line.style = "longdash"
chips-7> ci.line.color = "blue"
chips-8> ci.symbol.color = "magenta"
chips-9> set_curve(ci)
chips-10> split(2,1,0.1)
chips-11> adjust_grid_yrelsize (1, 2)
chips-12> x = numpy.arange(1,10,0.1)
chips-13> y = numpy.sin(x)
chips-14> add_curve(x,y,["line.color","magenta","symbol.style","none"])
chips-15> set_plot_xlabel("x_2")
chips-16> set_plot_ylabel("y_2")
chips-17> set_axis(["label.size",18,"label.color","magenta"])
chips-18> current_plot("plot1")
chips-19> set_plot_xlabel(r"\eta");      
chips-20> set_plot_ylabel("rate (count s^{-1})")
chips-21> set_axis(["label.size",18])
chips-22> set_xaxis(["offset.perpendicular",35])
chips-23> print_window("plot2")

Preferences and Histograms

This example show how you set preferences and draw histograms (i.e. how to convert the STEP command).

CIAO 3.4 output	CIAO 4.0 output

The four major differences in these plots are:

The histogram can be filled with a solid color, in this case green.
The histogram edges are now drawn down to y=0.
The auto scaling now considers the edges of the bins rather than the bin centers (which is why the X axis now goes up to 50).
The symbol is now drawn on top of the line, not the other way around.

CIAO 3 command language

unix% chips

Welcome to ChIPS, version CIAO 3.4
Copyright (C) 1999-2003, Smithsonian Astrophysical Observatory

chips> chips.symbolstyle = _chips->soliddiamond
chips> chips.symbolcolor = _chips->blue
chips> chips.curvecolor = _chips->red
chips> chips.curvestyle = _chips->step
chips> curve sample.txt x 1 y 2
chips> longdash

CIAO 4 Python version

unix% chips
chips-1> pr = ChipsHistogram()
chips-2> pr.symbol.style = "diamond"
chips-3> pr.symbol.fill = True
chips-4> pr.symbol.color = "blue"
chips-5> pr.line.color = "red"   
chips-6> set_preferences(pr)  
chips-7> add_histogram("sample.txt[cols x,y]")
chips-8> set_histogram(["line.style","longdash","fill.visible",1,"fill.color","green"])

If you only wanted to override the preferences for the add_histogram call - so that future calls use the original preference settings - then you would say

add_histogram("sample.txt[cols x,y]",pr)

instead of lines 6 and 7 above.