Plot phase diagram data

Plot data only

When compiling ESPEI datasets of phase equilibria data, it can be useful to plot the data to check that it matches visually with what you are expecting. This script plots data from a binary phase diagram.

import matplotlib.pyplot as plt
from pycalphad import variables as v
from espei.datasets import recursive_glob, load_datasets
from espei.plot import dataplot

# load datasets from directory
ds = load_datasets(recursive_glob("input-data"))

components = ["CU", "MG", "VA"]
independent_component = components[1]
phases = ["BCC_A2", "CUMG2", "FCC_A1", "LAVES_C15", "LIQUID"]
# Conditions don't need to have valid values.
# Only the keys matter because they are used to search for relevant data.
conds = {v.P: 101325, v.T: (1,1,1), v.X(independent_component): (1, 1, 1)}

fig, ax = plt.subplots()
dataplot(components, phases, conds, ds, ax=ax)
ax.set_xlim(0, 1)
ax.set_xlabel(f"X({independent_component.capitalize()})")
ax.set_ylabel(f"Temperature (K)")
ax.set_title("Cu-Mg Data")
fig.show()

Plot phase diagram with data

This example uses binplot from PyCalphad and dataplot from ESPEI to plot a phase diagram with the data used to fit it on the same axes.

import matplotlib.pyplot as plt
from pycalphad import Database, binplot, variables as v
from espei.datasets import load_datasets, recursive_glob
from espei.plot import dataplot

# load datasets from directory
datasets = load_datasets(recursive_glob("input-data"))

# set up the pycalphad phase diagram calculation
dbf = Database("Cr-Ni_mcmc.tdb")
comps = ["CR", "NI", "VA"]
phases = list(dbf.phases.keys())
conds = {v.P: 101325, v.T: (700, 2200, 10), v.X("CR"): (0, 1, 0.01)}

# plot the phase diagram and data
fig, ax = plt.subplots()
binplot(dbf, comps, phases, conds, plot_kwargs=dict(ax=ax))
dataplot(comps, phases, conds, datasets, ax=ax)
ax.set_title("Cr-Ni MCMC")
ax.set_ylim(conds[v.T][0], conds[v.T][1])
ax.set_xlabel("X(Cr)")
ax.set_ylabel("Temperature (K)")
fig.show()