Normalize Assay Channels

Use the Geochem Analysis > GeochemUtilities > Normalize Assay Channels option (CHNORM GX) to normalize one or more ASSAY class channels.

Normalize ASSAY channels dialog options

Channels to normalize

"All ASSAY channels" – all channels that are members of the ASSAY class will be normalized

"Displayed ASSAY channels" – only displayed channels that are members of the ASSAY class will be normalized.

"Select ASSAY channels from list" -- select ASSAY class channels from a two-panel selection list.

NOTE: Previously normalized channels are not included among the available channels, and are excluded from the selection list, even though they are assigned the "ASSAY" class. If you really want to normalize an already normalized channel, rename it to something that doesn’t end in "_N".

Script Parameter: CHNORM.CHANNELS: One of "ASSAY", "DISPLAYED_ASSAY" or "LIST"

Range

Value are multiplied by a factor to lie between 0 and the input range. Normal values are 1.0 or 100.0.

Script Parameter: CHNORM.RANGE (default: 1.0)

Outliers

Sets how outlier values are handled. This only affects those channels whose "Outlier limit" attribute is set.

Include: No special treatment is accorded outliers. They are scaled along with the rest of the values; so if values are normalized to be between 0 and 1, then outlier values will be greater than 1.0.

Clip: Outlier values are assigned the maximum range value.

Dummy: Outlier values are set to dummy in the new channel.

Script Parameter: CHNORM.OUTLIERS: 0:Include, 1:Clip, 2:Dummy

Application Notes

The CHNORM GX creates a new, normalized channel by adding "_N" to the selected channels. It normalizes the data using the following steps (R = defined output range):

  1. Determine the maximum value in the data ("Max")

  2. Get the outlier limit ("Out")

  3. If no outlier limit is defined, or if the maximum data value is less than the outlier limit, then multiply all the data by R./Max.

  4. If an outlier is defined, and it is less than the maximum data value, multiply all the data by R/Out.