Add covariance matrix sum plot

validphys2/src/validphys/theorycovariance/construction.py

@@ -697,6 +697,13 @@ def experimentplustheory_normcovmat_custom(
 
     return mat
 
+@table
+def experimentplustheory_covmat_singleprocess(procs_covmat, theory_covmat_singleprocess):
+    """Calculates the covariance matrix for the experimental
+    plus theory covariance matrices."""
+    total_df = procs_covmat + theory_covmat_singleprocess
+    total_cov = (procs_covmat + theory_covmat_singleprocess).values
+    return total_cov
 
 @table
 def experimentplustheory_corrmat_singleprocess(procs_covmat, theory_covmat_singleprocess):

validphys2/src/validphys/theorycovariance/output.py

@@ -323,6 +323,22 @@ def plot_expplusblockthcorrmat_heatmap(experimentplusblocktheory_corrmat):
     )
     return fig
 
+@figure
+def plot_expplusthcovmat_heatmap_custom(
+    experimentplustheory_covmat_custom,
+    theoryids,
+    fivetheories,
+):
+    """Matrix plot of the exp + theory covariance matrix"""
+    l = len(theoryids)
+    if l == 5:
+        if fivetheories == "bar":
+            l = r"$\bar{5}$"
+    fig = plot_covmat_heatmap(
+        experimentplustheory_covmat_custom,
+        f"Experimental + Theory Covariance Matrix ({l} pt)",
+    )
+    return fig
 
 @figure
 def plot_expplusthcorrmat_heatmap_custom(