diff --git a/mathics/builtin/comparison.py b/mathics/builtin/comparison.py
index e083bf48fb..7b225fb251 100644
--- a/mathics/builtin/comparison.py
+++ b/mathics/builtin/comparison.py
@@ -652,10 +652,9 @@ def _op(x):
class Unequal(_EqualityOperator, SympyComparison):
- """
+ u"""
- - 'Unequal[$x$, $y$]'
-
- '$x$ != $y$'
+
- 'Unequal[$x$, $y$]' or $x$ != $y$ or $x$ \u2260 $y$
- is 'False' if $x$ and $y$ are known to be equal, or
'True' if $x$ and $y$ are known to be unequal.
Commutative properties apply so if $x$ != $y$ then
@@ -667,15 +666,19 @@ class Unequal(_EqualityOperator, SympyComparison):
>> 1 != 1.
= False
+ Comparsion can be chained:
+ >> 1 != 2 != 3
+ = True
+
+ >> 1 != 2 != x
+ = 1 != 2 != x
+
Strings are allowed:
Unequal["11", "11"]
= False
- Equal["121", "11"]
- = True
-
Comparision to mismatched types is True:
- Equal[11, "11"]
+ Unequal[11, "11"]
= True
Lists are compared based on their elements:
@@ -723,16 +726,19 @@ def _op(x):
class Less(_ComparisonOperator, SympyComparison):
"""
- - 'Less[$x$, $y$]'
-
- '$x$ < $y$'
-
- yields 'True' if $x$ is known to be less than $y$.
-
- '$lhs$ < $rhs$'
-
- represents the inequality $lhs$ < $rhs$.
+
- 'Less[$x$, $y$]' or $x$ < $y$
+
- yields 'True' if $x$ is known to be less than $y$.
- #> {Less[], Less[x], Less[1]}
- = {True, True, True}
+ LessEqual operator can be chained:
+ >> LessEqual[1, 3, 3, 2]
+ = False
+
+ >> 1 < 3 < 3
+ = False
+ >> 1 < 3 < x < 2
+ = 1 < 3 < x < 2
"""
operator = "<"
@@ -740,32 +746,37 @@ class Less(_ComparisonOperator, SympyComparison):
class LessEqual(_ComparisonOperator, SympyComparison):
- """
-
- - 'LessEqual[$x$, $y$]'
-
- '$x$ <= $y$'
-
- yields 'True' if $x$ is known to be less than or equal to $y$.
-
- '$lhs$ <= $rhs$'
-
- represents the inequality $lhs$ $rhs$.
-
+ u"""
+
+ - 'LessEqual[$x$, $y$, ...]' or $x$ <= $y$ or $x$ \u2264 $y$
+
- yields 'True' if $x$ is known to be less than or equal to $y$.
+
+
+ LessEqual operator can be chained:
+ >> LessEqual[1, 3, 3, 2]
+ = False
+
+ >> 1 <= 3 <= 3
+ = True
+
"""
operator = "<="
- sympy_name = "LessThan"
+ sympy_name = "LessThan" # in contrast to StrictLessThan
class Greater(_ComparisonOperator, SympyComparison):
"""
- - 'Greater[$x$, $y$]'
-
- '$x$ > $y$'
-
- yields 'True' if $x$ is known to be greater than $y$.
-
- '$lhs$ > $rhs$'
-
- represents the inequality $lhs$ > $rhs$.
+
- 'Greater[$x$, $y$]' or '$x$ > $y$'
+
- yields 'True' if $x$ is known to be greater than $y$.
+
+ Greater operator can be chained:
>> a > b > c //FullForm
= Greater[a, b, c]
- >> Greater[3, 2, 1]
+
+ >> 3 > 2 > 1
= True
"""
@@ -776,12 +787,10 @@ class Greater(_ComparisonOperator, SympyComparison):
class GreaterEqual(_ComparisonOperator, SympyComparison):
"""
- - 'GreaterEqual[$x$, $y$]'
-
- '$x$ >= $y$'
-
- yields 'True' if $x$ is known to be greater than or equal
+
- 'GreaterEqual[$x$, $y$]'
+
- $x$ \u2256 $y$ or '$x$ >= $y$'
+
- yields 'True' if $x$ is known to be greater than or equal
to $y$.
-
- '$lhs$ >= $rhs$'
-
- represents the inequality $lhs$ $rhs$.
"""