This section gives a summary of the ICL language syntax. Square brackets imply that the enclosed part of the construct is optional.
Statements are executed as they are entered.
Statements are first entered into a procedure, then the procedure is executed.
See below.
1 | ** |
2 | * / |
3 | + - |
4 | = > < >= <= <> : |
5 | NOT AND OR & |
Normally one statement per line. A tilde (~) at the end of a line indicates that the statement continues on the next line.
These statements can be used in any operational mode.
Any line starting with the characters ‘{’ or ‘;’.
= expression (prints value of expression)
variable = expression (assignment to variable)
command_name p1 p2 …(command or procedure call)
In commands or procedure calls, parameters are separated by a comma or spaces. Expressions or variables should be enclosed in parentheses.
These statements can only be used in the Procedure operational mode.
You can escape from a loop via a BREAK statement.
The commands which are likely to be of most use in data analysis are classified below. Commands relevant mainly to data acquisition are omitted. A full list is contained in SG/5.
The following functions are available for use in expressions (N.B. The ‘$\ast $’ symbol in the Type column stands for ‘Real or Integer’).
Name | Type | Definition |
SIN(X) | Real | Trig. functions (x in radians). |
COS(X) | Real | |
TAN(X) | Real | |
SIND(X) | Real | Trig. functions (x in degrees). |
COSD(X) | Real | |
TAND(X) | Real | |
ASIN(X) | Real | ${sin}^{-1}x\phantom{\rule{2.77695pt}{0ex}}where-1\le x\le 1$; $-\pi /2\le result\le \pi /2$. |
ACOS(X) | Real | ${cos}^{-1}x\phantom{\rule{2.77695pt}{0ex}}where-1\le x\le 1$; $0\le result\le \pi $. |
ATAN(X) | Real | ${tan}^{-1}x$; $-\pi /2\le result\le \pi /2$. |
ATAN2(X1,X2) | Real | ${tan}^{-1}\left({x}_{1}/{x}_{2}\right)$; $-\pi <result\le \pi $. |
ASIND(X) | Real | Inverse trig functions in degrees. |
ACOSD(X) | Real | |
ATAND(X) | Real | |
ATAN2D(X1/X2) | Real | |
SINH(X) | Real | Hyperbolic functions. |
COSH(X) | Real | |
TANH(X) | Real | |
ABS(X) | * | $\mid x\mid $. |
DIM(X1,X2) | * | Positive difference between ${x}_{1}$ and ${x}_{2}$. |
EXP(X) | Real | ${e}^{x}$. |
LOG(X) | Real | $lnx$. |
LOG10(X) | Real | ${log}_{10}x$. |
MIN(X1,X2,...) | * | Minimum of two or more arguments. |
MAX(X1,X2,...) | * | Maximum of two or more arguments. |
MOD(X1,X2) | * | Remainder when ${x}_{1}$ is divided by ${x}_{2}$. |
SIGN(X1,X2) | * | Transfer of sign $\mid {x}_{1}\mid $ Sign ${x}_{2}$. |
SQRT(X) | Real | $\sqrt{x}$. |
BIN(I,n,m) | String | Integer I formatted in binary into an n char string |
with m significant digits. | ||
DEC(I,n,m) | String | Integer I formatted in decimal into an n char string |
with m significant digits. | ||
HEX(I,n.m) | String | Integer I formatted in hexadecimal into an n char string |
with m significant digits. | ||
OCT(I,n,m) | String | Integer I formatted in octal into an n char string |
with m significant digits. | ||
DECL(S) | Real | Declination in radians from string in degrees, minutes, seconds. |
DEC2S(R,NDP,SEP) | String | String in DMS with separator SEP and NDP decimal places |
on seconds, from Dec in radians. | ||
RA(S) | Real | Right Ascension in radians from a string in hours, minutes, seconds. |
RA2S(R,NDP,SEP) | String | String in HMS with separator SEP and NDP decimal places |
on seconds, from RA in radians. | ||
CHAR(I) | String | Character with ASCII value I. |
ICHAR(S) | Integer | ASCII value of first character of string S. |
INDEX(S1,S2) | Integer | Position of first occurrence of string S2 in string S1. |
LEN(S) | Integer | Length of string. |
ELEMENT(I,DELIM,S) | String | Ith element of delimited string. |
SUBSTR(S,n,m) | String | Substring of S beginning at n of length m. |
SNAME(S,n,m) | String | Name derived by concatenating string S with integer n |
formatted into m characters including leading zeros. | ||
UPCASE(S) | String | String S converted to upper case. |
LGE(S1,S2) | Logical | True if S1 $\ge $ S2 (ASCII collating sequence). |
LGT(S1,S2) | Logical | True if S1 $>$ S2 (ASCII collating sequence). |
LLE(S1,S2) | Logical | True if S1 $\le $ S2 (ASCII collating sequence). |
LLT(S1,S2) | Logical | True if S1 $<$ S2 (ASCII collating sequence). |
IAND(I1,I2) | Integer | Bitwise AND. |
IOR(I1,I2) | Integer | Bitwise OR. |
IEOR(I1,I2) | Integer | Bitwise Exclusive OR. |
INOT(I) | Integer | Bitwise Complement. |
FLOAT(I) | Real | Integer I converted to real. |
IFIX(X) | Integer | X converted to integer by truncation. |
INT(X) | Integer | X converted to integer by truncation. |
NINT(X) | Integer | Nearest integer to X. |
INTEGER(X) | Integer | X converted to integer. |
LOGICAL(X) | Logical | X converted to logical. |
REAL(X) | Real | X converted to real. |
STRING(X) | String | X converted to string. |
TYPE(X) | String | The type of X (‘REAL’, ‘INTEGER’, ‘LOGICAL’, |
‘STRING’, or ‘UNDEFINED’). | ||
UNDEFINED(X) | Logical | TRUE if X is undefined. |
DATE() | String | Current date. |
TIME() | String | Current time. |
GETNBS(S) | Any | Value of noticeboard item. |
GET_SYMBOL(S) | String | Value of DCL symbol. |
INKEY() | Integer | Key value of last key trapped (Screen mode only). |
KEYVALS(S) | Integer | Value of key with name S. |
OK(stat) | Logical | True if VMS Status OK. |
FILE_EXISTS(S) | Logical | True if file S exists. |
RANDOM(I) | Real | Random number between 0 and 1 from seed variable I. |
VARIABLE(proc,X) | Any | Returns value of variable X of procedure proc. |
Name | Description |
ADAMERR | An error has occurred in an ADAM task. An associated message will be output. |
ASSNOTVAR | An assignment has been made to a procedure formal parameter which does |
not correspond to a variable in the procedure call. | |
CLOSEERR | Error closing text file. |
CONVERR | Error converting RA or Dec to string or vice versa. |
CTRLC | A Control-C has been entered on the terminal. |
DEVERR | Error allocating or mounting device. |
EDITERR | Attempt to use the LSE or TPU editors when they are not available. |
EOF | End of file encountered on text file operation. |
FIGERR | Error in a FIGARO program, or FIGARO not available. |
FLTDIV | Floating point division by zero. |
FLTOVF | Floating point overflow. |
IFERR | The expression in an IF or ELSE IF statement does not evaluate to a logical value. |
INTOVF | Integer overflow. |
INVARGMAT | Invalid argument to a mathematical function. |
INVSET | Invalid SET command. |
LOGZERNEG | Logarithm of zero or negative number. |
NBSERR | Error in GETNBS or PUTNBS. |
OPENERR | Error opening text file. |
OPNOTLOG | Operands of a logical operator (AND, OR etc.) are not logical values. |
OPNOTNUM | Operands of a formatting operation (:) are not numeric. |
PROCERR | Unrecognized procedure or command name. |
READERR | Error reading from text file. |
RECCALL | Attempt to make a recursive call of a procedure. |
SCREENERR | Error in screen mode I/O. |
SQUROONEG | Square root of negative number. |
STKOVFLOW | ICL’s stack has overflowed. |
STKUNDFLOW | ICL stack underflow — if this occurs it indicates an internal error in ICL. |
TOOFEWPARS | Not enough parameters for a function or command. |
TOOMANYPARS | Too many parameters for a procedure or command. |
UNDEFVAR | Attempt to use an undefined variable — i.e. one that has not yet had a value assigned. |
UNDEXP | Undefined Exponentiation. |
USERERR | Error accessing a routine defined using DEFUSER, or error during such a routine. |
WHILEERR | The expression in a WHILE statement does not evaluate to a logical value. |
WRITERR | Error writing to text file. |