LOOKDOWN - Revision history

Admin: Created page with "= Action = Returns the index of a series of data.
2013-02-11T20:16:26Z

Created page with "= <span class="f_Header">Action</span> = Returns the index of a series of data. <span style="font-family: Arial;"> </span> <span style="font-family: Arial;"> </sp..."

New page
= <span class="f_Header">Action</span> =

Returns the index of a series of data.

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= <span class="f_Header">Syntax</span> =

var = <span class="f_Syntax">LOOKDOWN</span>( value, label, entries)

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= <span class="f_Header">Remarks</span> =
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{| width="488" cellspacing="0" cellpadding="1" border="1" style="border: 2px solid rgb(0, 0, 0); border-spacing: 0px; border-collapse: collapse;"
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Var

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The returned index value

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Value

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The value to search for

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Label

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The label where the data starts

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entries

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The number of entries that must be searched

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When you want to look in BYTE series the VALUE variable must be dimensioned as a BYTE. When you want to look in INTEGER or WORD series the VALUE variable must be dimensioned as an INTEGER.

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The LookDown function is the counterpart of the LookUp function.

Lookdown will search the data for a value and will return the index when the value is found. It will return –1 when the data is not found.

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= <span class="f_Header">See also</span> =

[[LOOKUPSTR]] , [[LOOKUP]]

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= <span class="f_Header">Example</span> =

<br/><source lang="bascomavr">
'-----------------------------------------------------------------------------------------
'name : lookdown.bas
'copyright : (c) 1995-2005, MCS Electronics
'purpose : demo : LOOKDOWN
'micro : Mega48
'suited for demo : yes
'commercial addon needed : no
'-----------------------------------------------------------------------------------------

$regfile = "m48def.dat" ' specify the used micro
$crystal = 4000000 ' used crystal frequency
$baud = 19200 ' use baud rate
$hwstack = 32 ' default use 32 for the hardware stack
$swstack = 10 ' default use 10 for the SW stack
$framesize = 40 ' default use 40 for the frame space

Dim Idx As Integer , Search As Byte , Entries As Byte

'we want to search for the value 3
Search = 3
'there are 5 entries in the table
Entries = 5

'lookup and return the index
Idx = Lookdown(search , Label , Entries)
Print Idx

Search = 1
Idx = Lookdown(search , Label , Entries)
Print Idx

Search = 100
Idx = Lookdown(search , Label , Entries)
Print Idx ' return -1 if not found

'looking for integer or word data requires that the search variable is
'of the type integer !
Dim Isearch As Integer
Isearch = 400
Idx = Lookdown(isearch , Label2 , Entries)
Print Idx ' return 3
End

Label:
Data 1 , 2 , 3 , 4 , 5

Label2:
Data 1000% , 200% , 400% , 300%
</source><br/>{{Languages}}

[[Category:BASCOM Language Reference]]