Zbex assignment statements - Revision history

Craig: added chapter navigator at top of page

2010-10-15T06:07:06Z

added chapter navigator at top of page

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			{{ZbexChap
			\| before = [[Zbex variable declaration statements\|Variable declaration statements]]
			\| after = [[Zbex run and stop statements\|The run and stop statements]]
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	The most common way to set the value of a variable is with an assignment statement. Assignment statements take the form <variable> = <expression>. The two sides of an assignment statement must have data types of the same type. The expression on the right may have one or more elements. For strings and bit strings, elements in an expression are combined using the concatenate operator (<tt> // </tt>). For integers and real numbers, elements are combined using one or more of the arithmetic operators:		The most common way to set the value of a variable is with an assignment statement. Assignment statements take the form <variable> = <expression>. The two sides of an assignment statement must have data types of the same type. The expression on the right may have one or more elements. For strings and bit strings, elements in an expression are combined using the concatenate operator (<tt> // </tt>). For integers and real numbers, elements are combined using one or more of the arithmetic operators:

Craig at 05:42, 15 October 2010

2010-10-15T05:42:08Z

← Older revision		Revision as of 05:42, 15 October 2010
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	In this case, the value of a is 11.		In this case, the value of a is 11.




			{{ZbexChap
			\| before = [[Zbex variable declaration statements\|Variable declaration statements]]
			\| after = [[Zbex run and stop statements\|The run and stop statements]]
			}}

Craig: created page

2010-10-13T14:57:10Z

created page

New page

__TOC__

The most common way to set the value of a variable is with an assignment statement. Assignment statements take the form <variable> = <expression>. The two sides of an assignment statement must have data types of the same type. The expression on the right may have one or more elements. For strings and bit strings, elements in an expression are combined using the concatenate operator (<tt> // </tt>). For integers and real numbers, elements are combined using one or more of the arithmetic operators:

<center>
{| class="wikitable" cellpadding="10" cellspacing="0" border="1"
|- {{Style|table header}}
! scope="col" | integer and real
! scope="col" | integer only
|-
|<tt>+</tt> = add <tt>-</tt> = substract <tt>*</tt> = multiply <tt>/</tt> = divide || <tt>&</tt> = and <tt><nowiki>|</nowiki></tt> = or <tt>>></tt> = shift right <tt><<</tt> = shift left
|}
</center>

In the absense of parentheses, arithmetic operators are processed in a left to right fashion, i.e., not according to the rules of algebra.

An element of an expression may be a literal, a variable or a function. Functions will be covered later. Examples:

=== Strings ===

str temp.80,name.80

name = "<your name>"
temp = "Good afternoon, " // name // ", I am pleased "
temp = temp // "to meet you."

In this case, the string temp has the value

Good afternoon, <your name>, I am pleased to meet you.

Note that the concatenate operator (<tt> // </tt>) must have a blank on either side of it.

=== Bit strings ===

bstr test1.80, test2.80

test1 = "1010101"
test2 = test1 // "000" // test1

In this case, the bit string test2 has the value 10101010001010101.

=== Intergers ===

int a,b,c

a = 10
b = 20
c = a >> 2 * b + 4

In this case, the value of c is 10 shifted right 2 = 2, times 20 = 40 plus 4 = 44.

=== Real numbers ===

real x,y,z

x = 10.0
y = 5.0
z = x - 3.0 / y * 3.0

In this case, the value of z is 10.0 minus 3.0 = 7.0, divided by 5.0 = 1.40, time 3.0 = 4.2

For interger and real number operations, you can use parentheses to control the order in which operations are performed.

For all assignment statements the right-hand side is evaluated before the left-hand side is changed. Examples:

bstr test1.80

test1 = "1010101"
test1 = test1 // "000" // test1

In this case, the bit string test1 has the value 10101010001010101.

int a

a = 10
a = a + 1

In this case, the value of a is 11.