Python Value Ranges
Information- The following Python methods can be defined in the attribute Wertebereich of all Dataitems.
- They are used to calculate or process the value of a Dataitem.
- You can use the full spectrum of methods available in the Python-API.
List of functions
| Method | Parameter | Return value | Comment |
|---|---|---|---|
| computeSqlValueRange(dt_name) | dt_name: String (SQL Alias which PLANTA uses for selecting the current record) | The return value of this function is used as a subselect in the original select for this table. So when ever PLANTA selects the current record it embeds the return value of this function to it's initial select as a subquery. Since PLANTA uses aliases as table names, the function receives the currently used table alias as input parameter | User defined method is called before the selection process for the current table takes place. |
| computeOutput(di) | di: Dataitem | processed new value of the same type as the DI's type | User defined method is called for output value computation. If the DI is of string type and length of compute value exceeds DB length of respective DI, the computed value will be trimmed to fit in. |
| checkInput(di, oldValue) | di: Dataitem (current DI) oldValue:same type as the DI's type (old value of DI) |
boolean value that says if check was successful | User defined method checks the validity of entered value. |
| processInput(di, oldValue) | di: Dataitem (current DI) oldValue:same type as the DI's type (old value of DI) |
processed new value of the same type as the DI's type | User defined method is called during setting of the new value and allow to perform some other action than only simple assigning of the value. Note: When an incarnation DI has a processInput() value range on both sub-DIs only the processInput() of the sub-DI with function "ID" is executed when inserting something in this field. |
Dependency tracking
Information- Since it's impossible to "auto-detect" all the possible source data references of the respective function it's necessary to specify them.
- Every function has an dependency attribute,
depswhich contains a tuple of DI source data references. PLANTA then can assure that all references are available when ever this DI is calculated. - Special Feature of the computeOutput function:
- The function is called whenever a source reference changes, this means that the result of the computeOutput function is always up to date according to its source references.
- Following functions must have dependencies:
- computeOutput()
- processInput()
- checkInput()
- the tuple of dependencies can contain
- DI references (DIs from the same record): ‘DI000123'
- Variable references (@G, @D, @L, @M): ‘@G15','@L1'
- '*' meaning that the value has to be recalculated in any case
- It's not necessary to add the DI containing the value range to the dependencies.
- Example: when the computeOutput() is customized on DI123456 it's not necessary to add DI123456 to the dependencies.
- If the DI only interacts with itself, simply add
deps= ('',) - If there's only one DI in the dependency add
deps= ('DI012345',)
import random
def computeOutput(di):
list = ppms.uvar_get('@M6')
return random.choice(list)
computeOutput.deps = ('@M6',) - in this case, computeOutput() depends on @M6 variable
Examples
checkInput
def checkInput(di, oldvalue):
rec = di.get_dtp_record()
compl_in_perc=rec.compl_in.get_value() #DI040154
compl_on=rec.compl_on.get_value() #DI040155
compl_by=rec.compl_by.get_value() #DI040156
if oldvalue == 0:
if compl_in_perc > 99 and compl_on > 0 and compl_by != "":
return True
else:
return False
else:
return True
checkInput.deps = ('DI040154','DI040156','DI040155')computeOutput
def computeOutput(di):
rec = di.get_dtp_record()
panel_title = rec.get_di_by_id(57816).get_value()
mod_title = rec.get_di_by_id(1588).get_value()
if panel_title == None or panel_title == '':
return str(mod_title)
else:
return str(panel_title)
computeOutput.deps = ('DI057816','DI001588')processInput
def processInput(di, oldvalue):
dtpRec = di.get_dtp_record()
diVal = di.get_value()
name = dtpRec.name.get_value() #DI001589
dt_id = dtpRec.dt_title.get_value() #DI003389
if name == "":
dtpRec.name.set_string_value(str(dt_id))
else:
dtpRec.name.set_string_value(str(name))
return str(diVal)
processInput.deps = ('DI001589','DI003389')computeSqlValueRange
def computeSqlValueRange(dt_name):
"""Calculate the number of data area assignments"""
val = """
select count(*)
from DT406
where di000969={0}.di000198
""".format(dt_name)
return str(val) |
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