1. Write Tcl script to swap a set of character in two string [5]
Given: Two strings.
Task: To swap the set of characters in to strings.
Command used: string map
# s and t are variable having string in them.
2. Discuss variable substitution and command substitution in your words [5]
Command substitution.
If a word contains an open bracket
(``['') then Tcl performs command substitution. To do this it invokes the
Tcl interpreter recursively to process the characters following the open
bracket as a Tcl script. The script may contain any number of commands and must
be terminated by a close bracket (``]''). The result of the script (i.e. the
result of its last command) is substituted into the word in place of the
brackets and all of the characters between them. There may be any number of command
substitutions in a single word. Command substitution is not performed on words
enclosed in braces.
If a word contains a dollar-sign
(``$'') followed by one of the forms described below, then Tcl
performs variable substitution: the dollar-sign and the following
characters are replaced in the word by the value of a variable. Variable
substitution may take any of the following forms:
Name is the name of a scalar
variable; the name is a sequence of one or more characters that are a letter,
digit, underscore, or namespace separators (two or more colons).
Name gives the name of an array
variable and index gives the name of an element within that
array. Name must contain only letters, digits, underscores, and
namespace separators, and may be an empty string. Command substitutions,
variable substitutions, and backslash substitutions are performed on the
characters of index.
Name is the name of a scalar
variable. It may contain any characters whatsoever except for close braces.
There may be any number
of variable substitutions in a single word. Variable substitution is not
performed on words enclosed in braces.
3.Write Tcl script to find average of 10 numbers with
procedure [5]
# proc: Define a Tcl procedure.
# puts: Output a string to an I/O stream.
# foreach: Loop
construct over a list of values.
# expr: Evaluate a math expression.
# length: Return the number of elements in a list.
4. Write Tcl
script to sum only even number between 0-10 using foreach command [5]
# if: Conditional command. Allows else and elseif clauses.
# return: Return a value from a procedure.
5. Write Tcl
script for conversion of following with usage of format or/and procedure [10]
(a) a
decimal number to other number system
(b) an octal
number to other number system
# format: Format a string similar to C sprintf.
# %b- binary, %d – decimal, %x – hexa decimal , %o – octal
conversion.
