Plotting multiple graphs using index to data from array

Question

Using Version 5.2 patchlevel 2, I tried the following plot:

gnuplot> set xdata time
gnuplot> set timefmt "%s"
gnuplot> array lr_a[100];array lr_b[100]
gnuplot> plot "free.dat" using 2:(i=stringcolumn(0)+1,lr_a[i]=$13,lr_b[i]=$14,$10) with linesp title columnheader(1)
gnuplot> print i
13
gnuplot> print lr_a
[-452057.0,-178648.0,9568.53,10688.5,11016.6,11142.9,11137.5,12296.8,12467.0,-147009.0,-18170.2,-17176.1,-6493.16,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,]
gnuplot> print lr_b
[0.000292381,0.000119527,5.32936e-07,-1.75101e-07,-3.82532e-07,-4.62388e-07,-4.58968e-07,-1.19192e-06,-1.29956e-06,9.95245e-05,1.80699e-05,1.74415e-05,1.06875e-05,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,]

Now I want to add plots using those arrays:

j=1
gnuplot> replot "free.dat" using 2:(lr_a[j]+lr_b[j]*$2) with linesp title "LR#".j

It worked, however when I try to add more plots like this

gnuplot> j=j+1;replot "free.dat" using 2:(lr_a[j]+lr_b[j]*$2) with linesp title "LR#".j
gnuplot> j=j+1;replot "free.dat" using 2:(lr_a[j]+lr_b[j]*$2) with linesp title "LR#".j
gnuplot> print j
3

The plots are all the same, labeled LR#3.

Why is that so?

For reference, here's (a rather useless) free.dat:

/home   1581728983       51175       51175           0       51175           0           1       51175     10411.5     10411.5           0     10411.5           0           1     10411.5
/home   1581729050       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00976562     -452057  0.000292381    1.00299     10411.5
/home   1581729142       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00920748     -178648  0.000119527    0.83085     10411.5
/home   1581730106       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00799351     9568.53  5.32936e-07  0.0304721     10411.5
/home   1581730231       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00715961     10688.5  -1.75101e-07    -0.0133904     10411.5
/home   1581730248       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00654339     11016.6  -3.82532e-07     -0.033421     10411.5
/home   1581730649       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00606222     11142.9  -4.62388e-07    -0.0487386     10411.5
/home   1581730988       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00567332     11137.5  -4.58968e-07    -0.0582907     10411.5
/home   1581732515       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00552427     12296.8  -1.19192e-06     -0.228729     10411.5
/home   1581732849       51175       51175           0       51175           0           1       51175     10411.5     10411.5  0.00537109       12467  -1.29956e-06      -0.30963     10411.5
/home   1581733526       51175       51175           0       51175           0           1       51175     10412.4     10411.6    0.258446     -147009  9.95245e-05   0.578522     10411.8
/home   1581797054       51175       51175           0       51175           0           1       51175     10412.7     10411.7    0.406035    -18170.2  1.80699e-05   0.818011     10412.8
/home   1581799764       51175       51175           0       51175           0           1       51175     10412.7     10411.7    0.482222    -17176.1  1.74415e-05   0.884514     10412.8
/home   1581802740       51175       51175           0       51175           0           1       51175     10411.5     10411.7    0.469488    -6493.16  1.06875e-05   0.646611     10412.3

Ethan · Accepted Answer · 2020-02-15 23:24:20Z

3

replot does not act as you may think it does. It does not reproduce the previous plot; it creates a new plot by re-using the previous command. So the sequence of commands

j = j0
plot foo(j)
j = j+1
replot, foo(j)
j = j+1
replot, foo(j)

results in 3 copies of the same plot foo(j0+2)

If you want to compose a plot with successive values of k do not use replot. Instead do something like

 plot for [j = j0 : j0+2] foo(j)

answered Feb 15, 2020 at 23:24

Ethan

15.4k2 gold badges15 silver badges25 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

U. Windl Over a year ago

So it means the plot command is stored with the variables unsubstituted?

Ethan Over a year ago

Yes. The text of the previous plot command is stored and then used to create a longer version of the same command by appending a comma and the text following the "replot".

Collectives™ on Stack Overflow

Plotting multiple graphs using index to data from array

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related