@dseries/hptrend_, @dseries/mpower: remove duplicate branches in if/then/else statement

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src/@dseries/hptrend_.m

@@ -37,18 +37,10 @@ end
 o.data = sample_hp_filter(o.data, lambda);
 
 for i=1:vobs(o)
-    if isempty(o.ops{i})
-        if isempty(lambda)
-            o.ops(i) = {sprintf('hptrend(%s, [])', o.name{i})};
-        else
-            o.ops(i) = {sprintf('hptrend(%s, %s)', o.name{i}, num2str(lambda))};
-        end
+    if isempty(lambda)
+        o.ops(i) = {sprintf('hptrend(%s, [])', o.name{i})};
     else
-        if isempty(lambda)
-            o.ops(i) = {sprintf('hptrend(%s, [])', o.name{i})};
-        else
-            o.ops(i) = {sprintf('hptrend(%s, %s)', o.name{i}, num2str(lambda))};
-        end
+        o.ops(i) = {sprintf('hptrend(%s, %s)', o.name{i}, num2str(lambda))};
     end
 end
 

src/@dseries/mpower.m

@@ -39,11 +39,7 @@ if isnumeric(p) && isvector(p) && isdseries(o) && length(p)==nobs(o)
     q = copy(o);
     q.data = bsxfun(@power, o.data, p);
     for i=1:vobs(q)
-        if isempty(q.ops{i})
-            q.ops(i) = {sprintf('power(%s, %s)', q.name{i}, matrix2string(p))};
-        else
-            q.ops(i) = {sprintf('power(%s, %s)', q.name{i}, matrix2string(p))};
-        end
+        q.ops(i) = {sprintf('power(%s, %s)', q.name{i}, matrix2string(p))};
     end
     return
 end