git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@5265 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp 2010-11-18 18:30:31 +00:00
parent 7b842d7f45
commit 03dfe53a21
4 changed files with 60 additions and 52 deletions

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@ -121,7 +121,7 @@ clarity, you must enclose the entire expression in quotes.
</PRE>
<P>and Boolean operators:
</P>
<PRE>A == B, A != B, A < B, A <= B, A > B, A >= B, A && B, A || B
<PRE>A == B, A != B, A < B, A <= B, A > B, A >= B, A && B, A || B, !A
</PRE>
<P>Each A and B is a number or a variable reference like $a or ${abc},
or another Boolean expression.
@ -130,19 +130,21 @@ or another Boolean expression.
substituted for in the expression, else an error will be generated.
</P>
<P>Expressions are evaluated left to right and have the usual C-style
precedence: the 4 relational operators "<", "<=", ">", and ">=" have
the highest precedence; those 4 relational operators before the
remaining two relational operators "==" and "!="; those two relational
operators before the logical AND operator "&&"; and the AND operator
"&&" before the logical OR operator "||". Parenthesis can be used to
precedence: the unary logical NOT operator "!" has the highest
precedence, the 4 relational operators "<", "<=", ">", and ">=" are
next; the two remaining relational operators "==" and "!=" are next;
then the logical AND operator "&&"; and finally the logical OR
operator "||" has the lowest precedence. Parenthesis can be used to
group one or more portions of an expression and/or enforce a different
order of evaluation than what would occur with the default precedence.
</P>
<P>The 6 relational operators return either a 1.0 or 0.0 depending on
whether the relationship between x and y is true or false. The
whether the relationship between x and y is TRUE or FALSE. The
logical AND operator will return 1.0 if both its arguments are
non-zero, else return a 0.0. The logical OR operator will return 1.0
if either of its arguments is non-zero, else return a 0.0.
non-zero, else it returns 0.0. The logical OR operator will return
1.0 if either of its arguments is non-zero, else it returns 0.0. The
logical NOT operator returns 1.0 if its argument is 0.0, else it
returns 0.0.
</P>
<P>The overall Boolean expression produces a TRUE result if the result is
non-zero. If the result is zero, the expression result is FALSE.

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@ -117,7 +117,7 @@ An expression is built out of numbers:
and Boolean operators:
A == B, A != B, A < B, A <= B, A > B, A >= B, A && B, A || B :pre
A == B, A != B, A < B, A <= B, A > B, A >= B, A && B, A || B, !A :pre
Each A and B is a number or a variable reference like $a or $\{abc\},
or another Boolean expression.
@ -126,19 +126,21 @@ If a variable is used it must produce a number when evaluated and
substituted for in the expression, else an error will be generated.
Expressions are evaluated left to right and have the usual C-style
precedence: the 4 relational operators "<", "<=", ">", and ">=" have
the highest precedence; those 4 relational operators before the
remaining two relational operators "==" and "!="; those two relational
operators before the logical AND operator "&&"; and the AND operator
"&&" before the logical OR operator "||". Parenthesis can be used to
precedence: the unary logical NOT operator "!" has the highest
precedence, the 4 relational operators "<", "<=", ">", and ">=" are
next; the two remaining relational operators "==" and "!=" are next;
then the logical AND operator "&&"; and finally the logical OR
operator "||" has the lowest precedence. Parenthesis can be used to
group one or more portions of an expression and/or enforce a different
order of evaluation than what would occur with the default precedence.
The 6 relational operators return either a 1.0 or 0.0 depending on
whether the relationship between x and y is true or false. The
whether the relationship between x and y is TRUE or FALSE. The
logical AND operator will return 1.0 if both its arguments are
non-zero, else return a 0.0. The logical OR operator will return 1.0
if either of its arguments is non-zero, else return a 0.0.
non-zero, else it returns 0.0. The logical OR operator will return
1.0 if either of its arguments is non-zero, else it returns 0.0. The
logical NOT operator returns 1.0 if its argument is 0.0, else it
returns 0.0.
The overall Boolean expression produces a TRUE result if the result is
non-zero. If the result is zero, the expression result is FALSE.

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@ -44,7 +44,7 @@
constants = PI
thermo keywords = vol, ke, press, etc from <A HREF = "thermo_style.html">thermo_style</A>
math operators = (), -x, x+y, x-y, x*y, x/y, x^y,
x==y, x!=y, x<y, x<=y, x>y, x>=y, x&&y, x||y
x==y, x!=y, x<y, x<=y, x>y, x>=y, x&&y, x||y, !x
math functions = sqrt(x), exp(x), ln(x), log(x),
sin(x), cos(x), tan(x), asin(x), acos(x), atan(x), atan2(y,x),
random(x,y,z), normal(x,y,z), ceil(x), floor(x), round(x)
@ -272,7 +272,7 @@ references to other variables.
<TR><TD >Number</TD><TD > 0.2, 100, 1.0e20, -15.4, etc</TD></TR>
<TR><TD >Constant</TD><TD > PI</TD></TR>
<TR><TD >Thermo keywords</TD><TD > vol, pe, ebond, etc</TD></TR>
<TR><TD >Math operators</TD><TD > (), -x, x+y, x-y, x*y, x/y, x^y, x==y, x!=y, x<y, x<=y, x>y, x>=y, x&&y, x||y</TD></TR>
<TR><TD >Math operators</TD><TD > (), -x, x+y, x-y, x*y, x/y, x^y, x==y, x!=y, x<y, x<=y, x>y, x>=y, x&&y, x||y, !x</TD></TR>
<TR><TD >Math functions</TD><TD > sqrt(x), exp(x), ln(x), log(x), sin(x), cos(x), tan(x), asin(x), acos(x), atan(x), atan2(y,x), random(x,y,z), normal(x,y,z), ceil(x), floor(x), round(x), ramp(x,y), stagger(x,y), logfreq(x,y,z), vdisplace(x,y), swiggle(x,y,z), cwiggle(x,y,z)</TD></TR>
<TR><TD >Group functions</TD><TD > count(ID), mass(ID), charge(ID), xcm(ID,dim), vcm(ID,dim), fcm(ID,dim), bound(ID,dir), gyration(ID), ke(ID), angmom(ID,dim), inertia(ID,dimdim), omega(ID,dim)</TD></TR>
<TR><TD >Region functions</TD><TD > count(ID,IDR), mass(ID,IDR), charge(ID,IDR), xcm(ID,dim,IDR), vcm(ID,dim,IDR), fcm(ID,dim,IDR), bound(ID,dir,IDR), gyration(ID,IDR), ke(ID,IDR), angmom(ID,dim,IDR), inertia(ID,dimdim,IDR), omega(ID,dim,IDR)</TD></TR>
@ -325,26 +325,28 @@ scalars, where "vy+vz" is the element-by-element sum of two per-atom
vectors of y and z velocities.
</P>
<P>Operators are evaluated left to right and have the usual C-style
precedence: unary minus before exponentiation ("^"); exponentiation
before multiplication and division; multiplication and division before
addition and subtraction; addition and subtraction before the 4
relational operators "<", "<=", ">", and ">="; those 4 relational
operators before the remaining two relational operators "==" and "!=";
those two relational operators before the logical AND operator "&&";
and the AND operator "&&" before the logical OR operator "||".
Parenthesis can be used to group one or more portions of a formula
and/or enforce a different order of evaluation than what would occur
with the default precedence.
precedence: unary minus and unary logical NOT operator "!" have the
highest precedence, exponentiation "^" is next; multiplication and
division are next; addition and subtraction are next; the 4 relational
operators "<", "<=", ">", and ">=" are next; the two remaining
relational operators "==" and "!=" are next; then the logical AND
operator "&&"; and finally the logical OR operator "||" has the lowest
precedence. Parenthesis can be used to group one or more portions of
a formula and/or enforce a different order of evaluation than what
would occur with the default precedence.
</P>
<P>The 6 relational operators return either a 1.0 or 0.0 depending on
whether the relationship between x and y is true or false. For
whether the relationship between x and y is TRUE or FALSE. For
example the expression x<10.0 in an atom-style variable formula will
return 1.0 for all atoms whose x-coordinate is less than 10.0, and 0.0
for the others. The logical AND operator will return 1.0 if both its
arguments are non-zero, else return a 0.0. The logical OR operator
will return 1.0 if either of its arguments is non-zero, else return a
0.0. These relational and logical operators can be used as a masking
or selection operation in a formula. For example, the number of atoms
arguments are non-zero, else it returns 0.0. The logical OR operator
will return 1.0 if either of its arguments is non-zero, else it
returns 0.0. The logical NOT operator returns 1.0 if its argument is
0.0, else it returns 0.0.
</P>
<P>These relational and logical operators can be used as a masking or
selection operation in a formula. For example, the number of atoms
whose properties satifsy one or more criteria could be calculated by
taking the returned per-atom vector of ones and zeroes and passing it
to the <A HREF = "compute_reduce.html">compute reduce</A> command.

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@ -39,7 +39,7 @@ style = {delete} or {index} or {loop} or {world} or {universe} or {uloop} or {st
constants = PI
thermo keywords = vol, ke, press, etc from "thermo_style"_thermo_style.html
math operators = (), -x, x+y, x-y, x*y, x/y, x^y,
x==y, x!=y, x<y, x<=y, x>y, x>=y, x&&y, x||y
x==y, x!=y, x<y, x<=y, x>y, x>=y, x&&y, x||y, !x
math functions = sqrt(x), exp(x), ln(x), log(x),
sin(x), cos(x), tan(x), asin(x), acos(x), atan(x), atan2(y,x),
random(x,y,z), normal(x,y,z), ceil(x), floor(x), round(x)
@ -265,7 +265,7 @@ references to other variables.
Number: 0.2, 100, 1.0e20, -15.4, etc
Constant: PI
Thermo keywords: vol, pe, ebond, etc
Math operators: (), -x, x+y, x-y, x*y, x/y, x^y, x==y, x!=y, x<y, x<=y, x>y, x>=y, x&&y, x||y
Math operators: (), -x, x+y, x-y, x*y, x/y, x^y, x==y, x!=y, x<y, x<=y, x>y, x>=y, x&&y, x||y, !x
Math functions: sqrt(x), exp(x), ln(x), log(x), sin(x), cos(x), tan(x), asin(x), acos(x), atan(x), atan2(y,x), random(x,y,z), normal(x,y,z), ceil(x), floor(x), round(x), ramp(x,y), stagger(x,y), logfreq(x,y,z), vdisplace(x,y), swiggle(x,y,z), cwiggle(x,y,z)
Group functions: count(ID), mass(ID), charge(ID), xcm(ID,dim), \
vcm(ID,dim), fcm(ID,dim), bound(ID,dir), \
@ -324,26 +324,28 @@ scalars, where "vy+vz" is the element-by-element sum of two per-atom
vectors of y and z velocities.
Operators are evaluated left to right and have the usual C-style
precedence: unary minus before exponentiation ("^"); exponentiation
before multiplication and division; multiplication and division before
addition and subtraction; addition and subtraction before the 4
relational operators "<", "<=", ">", and ">="; those 4 relational
operators before the remaining two relational operators "==" and "!=";
those two relational operators before the logical AND operator "&&";
and the AND operator "&&" before the logical OR operator "||".
Parenthesis can be used to group one or more portions of a formula
and/or enforce a different order of evaluation than what would occur
with the default precedence.
precedence: unary minus and unary logical NOT operator "!" have the
highest precedence, exponentiation "^" is next; multiplication and
division are next; addition and subtraction are next; the 4 relational
operators "<", "<=", ">", and ">=" are next; the two remaining
relational operators "==" and "!=" are next; then the logical AND
operator "&&"; and finally the logical OR operator "||" has the lowest
precedence. Parenthesis can be used to group one or more portions of
a formula and/or enforce a different order of evaluation than what
would occur with the default precedence.
The 6 relational operators return either a 1.0 or 0.0 depending on
whether the relationship between x and y is true or false. For
whether the relationship between x and y is TRUE or FALSE. For
example the expression x<10.0 in an atom-style variable formula will
return 1.0 for all atoms whose x-coordinate is less than 10.0, and 0.0
for the others. The logical AND operator will return 1.0 if both its
arguments are non-zero, else return a 0.0. The logical OR operator
will return 1.0 if either of its arguments is non-zero, else return a
0.0. These relational and logical operators can be used as a masking
or selection operation in a formula. For example, the number of atoms
arguments are non-zero, else it returns 0.0. The logical OR operator
will return 1.0 if either of its arguments is non-zero, else it
returns 0.0. The logical NOT operator returns 1.0 if its argument is
0.0, else it returns 0.0.
These relational and logical operators can be used as a masking or
selection operation in a formula. For example, the number of atoms
whose properties satifsy one or more criteria could be calculated by
taking the returned per-atom vector of ones and zeroes and passing it
to the "compute reduce"_compute_reduce.html command.