joon's threads (merged) about random numbers

[dotJoon]

<cfoutput>
#RandRange(1, 5)#
</cfoutput>

The code above produces one of 1, 2, 3, 4, or 5 randomly.

I like to produce one of 1 or 5 randomly.

Is that a way to get one of 1 or 5 randomly?

[r937]

#RandRange(0,1)# * 4 + 1

[dotJoon]

data in myTable

(id) continent city
(1)    2       Rome
(2)    1       Peking
(3)    1       Seoul
(4)    2       Paris
(5)    1       Tokyo
(6)    3       New York
(7)    2       Berlin
(8)    3       Montreal

I have data in myTable like the above.

The following code1 produce the following result.

code1

select city
from myTable
where continent=1

result1

Peking
Seoul
Tokyo

The following would-be code doesn't work correctlyb but it will show what I want.

would-be code

select city(call 1 city randomly)
from myTable
where continent=1


target result

Peking, Seoul, or Tokyo(randomly)

Can I get my target result above with your help?

[dotJoon]

#RandRange(0,1)*4+1#

Thank you, the code works fine.

[dotJoon]

<cfoutput>
#RandRange(1, 10)#
</cfoutput>

The code above produces 1 random number from 1 to 10.

I like to produce 1 random number from 1 to 10 except 7 and 9.
( I like to produce 1,2,3,4,5,6,8, or 10.)

[r937]

<cfset joon = 7>
<cfloop condition = "joon EQ 7 OR joon EQ 9">
<cfset joon = RandRange(1,10)>
</cfloop>
<cfoutput>
#joon#
</cfoutput>

[dotJoon]

<cfset joon = 7>
<cfloop condition = "joon EQ 7 OR joon EQ 9">
<cfset joon = RandRange(1,10)>
</cfloop>
<cfoutput>
#joon#
</cfoutput>

Thank you. it works fine.


Now I have another question related this issue.
It's start from randon issue. but I like to ask you about how to put data value into list value.

<cfquery datasource='db2' name='test'>
select id
from myTable2
order by id
</cfquery>

<cfoutput>


<cfloop query='test'>
(#id#)<br>
</cfloop>

<cfloop query='test'>
<cfset 'id#currentRow#'=test.id>
</cfloop>

<cfset myList='#variables.id1#, #variables.id2#, #variables.id3#,#variables.id4#'>


<cfset randListElement = ListGetAt(mylist,RandRange(1,ListLen(myList))) >

<cfoutput>
#variables.randListElement#
</cfoutput>

The code above produce the data value randomly.
As I don't know much about list, I guess there might be easier way than the code above.


The code above produece a random value from the 4 variables.
If I need 40 or 400 data, do I have to write it like the below?

<cfset myList='#variables.id1#, #variables.id2#, #variables.id3#,#variables.id4#, ...
... #variables.id399#, #variables.id400#'>

[dotJoon]

I got it by myself.

ValueList(test.id) is the answer!!!

[dotJoon]

<cfset myList='1,3,4,7,9,12,15,18'>

#myList#

<cfset getOne_randomly = ListGetAt(mylist,RandRange(1,ListLen(myList))) >

The variable getOne_randomly produeces one number among numbers in myList.

I like to produce 3 numbers exclusively among numbers in myList.

[r937]

I got it by myself.

good job

[cfStarlight]

Assuming your list always has at least three elements, loop from 1 to 3. Within each loop, save the random element then remove it from the array to ensure it is not selected again. Add validation if your list may have less than 3 elements.

<cfset threeRandom = "">
<cfloop from="1" to="3" index="p">
	<cfset pos = RandRange(1,ListLen(myList))>
	<!--- save the random element --->
	<cfset threeRandom = listAppend(threeRandom, listGetAt(myList, pos))>
	<!--- remove the element --->
	<cfset mylist = ListDeleteAt(mylist, pos) >
</cfloop>

<cfoutput>#threeRandom#</cfoutput>

[cfStarlight]

I got it by myself.

ValueList(test.id) is the answer!!!

Doesn't your database have functions for ordering records randomly and limiting the number of records returned?

http://www.petefreitag.com/item/466.cfm

[longneck]

select city
from myTable
where continent=1
order by rand()
limit 1

[dotJoon]

select city
from myTable
where continent=1
order by rand()
limit 1

Thank you, CFStarLight and Longneck.