Problem in ploting keff

User Support
1

Hi,

I used the code in an example to plot keff, where the curve above is correct and I want, but why does the curve below appear? The code is as following.

results = openmc.deplete.ResultsList.from_hdf5(“./depletion_results.h5”)
time, k = results.get_eigenvalue()
days = 246060
plt.plot(time/days, k, label=“K-effective”)
plt.xlabel(“Time (days)”)
plt.ylabel(“Keff”)
plt.legend()
plt.show()

And the picture I get

image
image1020×781 22.7 KB

2

The array returned has two columns: column zero is the expected value, column one is the associated uncertainty. If you just wanted to plot k without uncertainty, run

plt.plot(time / days, k[:, 0], label="K-effective")

or, to plot with errorbars

plt.errorbar(time / days, k[:, 0], yerr=k[:, 1], label="K-effective")

Edit: add link to docs - openmc.deplete.ResultsList — OpenMC Documentation