Merge pull request #799 from benjeffery/remove-impute-language

Shift language on error and docs to replace 'impute'

Author: benjeffery

c/tskit/core.c

@@ -411,8 +411,8 @@ tsk_strerror_internal(int err)
             ret = "Must have at least one allele when specifying an allele map";
             break;
         case TSK_ERR_MUST_IMPUTE_NON_SAMPLES:
-            ret = "Cannot generate genotypes for non-samples unless missing data "
-                  "imputation is enabled";
+            ret = "Cannot generate genotypes for non-samples when isolated nodes are "
+                  "considered as missing";
             break;
         case TSK_ERR_ALLELE_NOT_FOUND:
             ret = "An allele was not found in the user-specified allele map";

docs/stats.rst

@@ -23,7 +23,7 @@ statistics API in use.
 
 .. warning:: :ref:`sec_data_model_missing_data` is not currently
    handled correctly by site statistics defined here, as we always
-   impute missing data to be equal to the ancestral state. Later
+   assign missing data to be equal to the ancestral state. Later
    versions will add this behaviour as an option and will account
    for the presence of missing data by default.