How do I access a specific value from a wave and take this one to appear in the legend?
| tatj | August 17, 2010 - 01:49 | ||
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I have a probably really easy-to-answer question, but I couldn't find an answer by myself (hard to get good keywords so a search gives the desired answer). I have series of data files where one is varied as a function of the other and a second one is kept fixed fro one measurement (one file). This second parameter varies only from one file to the next. All three values are written in a tab-separated text-file eg. So I measure B with respect to A, and C is the same for this file but will be different for the next file. In the graph I want now to have the value of C to appear as the legend. So fare I tried to define the wave accordingly by naming the string strIsd accordingly Thanks for any help macro loadVsd_varied() string /G path string /G head variable num string fname string strVg string strIsd string strVsd string nummer variable strlength display LoadWave/G/D/W/A/C fname=RemoveEnding(S_fileName,".txt") strlength = strlen(fname) num=str2num(fname[strlength-4,strlength]) head=fname[0,strlength-5] path=S_path do sprintf nummer "%*.*d" 1, 4, num fname = path + head + nummer + ".txt" strVg = "wv"+head+"Vg" + nummer strIleak = "wv"+head+"Ileak" + nummer strVsd = "wv"+head+"Vsd" + nummer strIsd = " "+head+ nummer sprintf strIsd "V\Bg\M =%.0W1PV"+strIsd ,wave2[0] duplicate /O wave0, $strVg duplicate /O wave1, $strIsd duplicate /O wave2, $strVsd killwaves wave0, wave1, wave2 append $strIsd vs $strVg num += 1 LoadWave/G/D/W/A/C fname while(V_flag>0) Legend end |
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Joined: 2010-06-30
Location: Switzerland
It came to my mind that the name just became too long. Does somebody know what the maximum allowed length is?
Joined: 2007-03-01
Location: United States
Wave names, as well as other Igor object names, can be up to 31 characters in length. But I think your problem is (also?) that your wave name contains characters such as a space and equals sign that require you to use liberal names, and to use liberal names you have to enclose the name in single quotes.
Execute the following commands on Igor's command line for more information:
Your life will be much easier if you refrain from ever using liberal wave and object names if that's possible.
Joined: 2007-06-21
Location: United States
The maximum length of a name is 31 characters.
Keep in mind that the error sometimes occurs in the line preceding the line that is highlighted when Igor reports the error.
By writing macros instead of functions, you are limiting what you can do in Igor programming, limiting execution speed, and not benefitting from compile-time checking of syntax. You can't use structures, switch statements, pass-by-reference parameters, for loops, free waves, data folder references and many other features. Also, all new features will be added to functions so the list of what you can not use will grow. So I recommend that you use functions instead of macros. Below is your macro rewritten as a function with comments indicating what I changed.
Also, it is better to pass parameters to a procedure rather than relying on global variables. I would pass the pre-existing waves (wave0, wave1, wave2) as parameters and also the strleak string variable which appears to be a global string variable. Or perhaps strleak does not need to be a global at all and should be a local variable.
To learn about functions, execute:
Joined: 2010-06-30
Location: Switzerland
Thanks for the answers.
Would there also be another/easier way to define the legend, then by using the wave names?
Joined: 2010-06-30
Location: Switzerland
By writing macros instead of functions, you are limiting what you can do in Igor programming, limiting execution speed, and not benefitting from compile-time checking of syntax.
What is then the actual difference between macros and functions? If you say I would better use functions, what are then macros for?
Joined: 2007-03-01
Location: United States
By writing macros instead of functions, you are limiting what you can do in Igor programming, limiting execution speed, and not benefitting from compile-time checking of syntax.
What is then the actual difference between macros and functions? If you say I would better use functions, what are then macros for?
Execute
DisplayHelpTopic "Comparing Macros And Functions"in Igor to bring up the documentation that details the differences. There is a bullet list in that topic. The summary is that in almost every way, functions are superior to macros. Therefore, unless you require a macro (such as a window recreation macro), write the code as a function instead.Macros existed before functions, so for backwards compatibility they still exist.