Radio Shack TRS-80 PC-3 Owner's Manual page 183

• As a rule, the error of functional calculations is less than ±1 at the lowest digit of a displayed numerical value (at the lowest
digit of mantissa in the case of scientific notation system) within the above calculation range.
Note: Power calculation is performed from m logx and
1Qx
calculations.
Y"X ~ 1
OX logy
Therefore, there is inevitably a difference, to some extent, from the true value in the computer. This difference does not
usually appear on the display. However, it is accumulated depending on calculation contents, such as continuous calcula-
tions, and may appear on the display.
Example; 16-2"2"2
(ENTER) ~
6.E-10
String Functions
String functions are a group of operations used for manipulating strings. Some take a string argument and return a numeric value.
Some take a string argumennt and return a string. Some take a numeric value and return a string. Some take a string argument
and one or two numeric arguments and return a string. Many dialects of BASIC require the argument of a function to be enclosed
in parentheses. The PC-3 does not require these parentheses, except when it is necessary to indicate what part of a more complex
expression is to be included in the argument. String functions with two or three arguments all require the parentheses. For
example, CH R$ 65
+
4 is interpreted as (CH R$ 65)
+
4, which is an illegal mixture of string and numeric quantities; CH R$ (65
+
4)
is valid.
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