PERF: increase the minimum number of elements to use numexpr for ops from 1e4 to 1e6 (#40502)

jorisvandenbossche · web-flow · commit bd8c79fa04ea · 2021-03-19T21:14:13.000-04:00
diff --git a/pandas/core/computation/expressions.py b/pandas/core/computation/expressions.py
@@ -40,7 +40,7 @@
 }
 
 # the minimum prod shape that we will use numexpr
-_MIN_ELEMENTS = 10000
+_MIN_ELEMENTS = 1_000_000
 
 
 def set_use_numexpr(v=True):
diff --git a/pandas/tests/test_expressions.py b/pandas/tests/test_expressions.py
@@ -12,7 +12,7 @@
 )
 from pandas.core.computation import expressions as expr
 
-_frame = DataFrame(np.random.randn(10000, 4), columns=list("ABCD"), dtype="float64")
+_frame = DataFrame(np.random.randn(1000000, 4), columns=list("ABCD"), dtype="float64")
 _frame2 = DataFrame(np.random.randn(100, 4), columns=list("ABCD"), dtype="float64")
 _mixed = DataFrame(
     {

Original file line number	Diff line number	Diff line change
`@@ -40,7 +40,7 @@`
`40`	`40`	`}`
`41`	`41`
`42`	`42`	`# the minimum prod shape that we will use numexpr`
`43`		`-_MIN_ELEMENTS = 10000`
	`43`	`+_MIN_ELEMENTS = 1_000_000`
`44`	`44`
`45`	`45`
`46`	`46`	`def set_use_numexpr(v=True):`
Original file line number	Diff line number	Diff line change
`@@ -12,7 +12,7 @@`
`12`	`12`	`)`
`13`	`13`	`from pandas.core.computation import expressions as expr`
`14`	`14`
`15`		`-_frame = DataFrame(np.random.randn(10000, 4), columns=list("ABCD"), dtype="float64")`
	`15`	`+_frame = DataFrame(np.random.randn(1000000, 4), columns=list("ABCD"), dtype="float64")`
`16`	`16`	`_frame2 = DataFrame(np.random.randn(100, 4), columns=list("ABCD"), dtype="float64")`
`17`	`17`	`_mixed = DataFrame(`
`18`	`18`	`{`