Formula
Workbench Help
All fields are listed alphabetically. The section of the Workbench containing the field is in parenthesis following the field name.
Actual (Formula Nutrient)
Actual is the amount of the nutrient that is actually in the formula solution after Solve.
Actual Pct (Formula Ingredient)
Actual Pct is the percent of the ingredient that is actually in the formula solution after Solve.
Actual Wgt (Formula Ingredient)
Actual Wgt is the weight of the ingredient that is actually in the formula solution after Solve.
Batch Weight (Formula)
Batch Weight is the target weight for the least-cost solution. Typically, it is a standard size of 1000 for metric system users and 2000 for English system users. Batch Weight is required.
It also could be the size of the batch mixer (say 5000) or even an individual daily intake size for an animal (say 30).
Its interpretation is affected by Dry Matter.
Reports such as Batch Mixer reports and the Formula Solution Report prompt for their own batch weight, so specifying a standard batch weight here does not limit the user later on in the system.
Code (Formula Nutrient)
Code is an alias for the nutrient that ensures compatibility with other systems.
Cost (Formula Ingredient)
Formula Ingredient Cost is derived from the Ingredient Cost. However, the Formula Ingredient Cost depends on the selected Cost Type for the Formula.
Cost (Formula Nutrient)
Formula Nutrient Cost is the savings to the Total Cost that can be realized if the nutrient constraint is changed by one unit.
If cost is positive, then if the maximum is increased by one unit, the total cost will decrease by approximately the cost. Also, if the maximum is increased by one tenth of a unit, the total cost will decrease by approximately one tenth of the cost.
If cost is negative, then if the minimum is decreased by one unit, the Total Cost will decrease by approximately the cost (regardless of the sign). Also, if the minimum is decreased by one tenth of a unit, the total cost will decrease by approximately one tenth of the cost (regardless of the sign).
Cost Type (Formula)
Ingredient Cost Type determines how cost will be calculated.
Enter one of the following:
Market for replacement cost. If zero, Cost will be used.
Market Only for replacement cost. If zero, zero will be used.
Cost for a second cost. It might contain a “cushion”, or it could be the actual cost, or it may be an artificially lower cost in order to use up an ingredient. If zero, Market will be used.
Cost Only for a second cost. If zero, zero will be used.
High for the higher of Market or Cost
Low for the lower of Market or Cost
Average for average Inventory cost.
Zero for zero cost. Can be used to "hide" costs on a report
On Farm is the sum of Cost plus ingredient margin. Used to price producer feeds that are mixed at the mill for the producer.
Dry Matter (Formula)
This is a one character field that determines if the solution nutrients and the Batch Weight will be considered as 100% dry matter. Solution ingredients will be printed “as is.”
Enter one of the following:
Y Solution Nutrients and Batch Weight as 100% dry matter.
N (default) Solution Nutrients and Batch Weight “as is.”
High Cost (Formula Ingredient)
This is the ingredient cost at which some of the ingredient will leave the solution, all other things kept the same.
Infeasible Solution (Formula)
A common tendency for the novice is to put restrictions on everything in sight, the tighter the better, compounding the mistake with the thought that every minimum needs a maximum, and vice versa!
Actually, the maxim "Less is More" should be followed by the user in setting up restrictions. Unnecessary restrictions not only limit the "trade-offs" available to the least-cost algorithm, thereby resulting in a solution that is more costly, but also can cause infeasibilites.
If you have no clues in "debugging" an infeasible solution, remove half the constraints and solve again, repeating until you have a feasible solution.
Then add back half of the constraints that you most recently discarded, repeating until you have isolated the culprit(s).
Ingredients (tab)
For ingredients, the minimum and maximum values are expressed in percent or in units of weight. Typical units are kg (kilograms), or lb (pounds).
In general, a nutrient restriction on salt is better than a restriction on a salt ingredient.
Log (Formula)
This is a one character field which permits the LP solution statistics to be logged on the screen.
Enter one of the following:
N (default) Do not Log LP statistics.
S Log LP statistics.
D Debug LP
Low Cost (Formula Ingredient)
This is the ingredient cost at which more of the ingredient will enter the solution, all other things kept the same.
Margin (Formula)
This is a one character field that permits margins to be printed on the solution.
Enter one of the following:
Y Print margins.
N (default) Do not print margins.
Max (Formula Nutrient)
Max is the maximum units of the nutrient that is desired in the formula solution.
Max Pct (Formula Ingredient)
Max Pct is the maximum percent of the ingredient that is desired in the formula solution.
Max Wgt (Formula Ingredient)
Max Wgt is the maximum weight of the ingredient that is desired in the formula solution.
Min (Formula Nutrient)
Min is the minimum units of the nutrient that is desired in the formula solution.
Min Pct (Formula Ingredient)
Min Pct is the minimum percent of the ingredient that is desired in the formula solution.
Min Wgt (Formula Ingredient)
Min Wgt is the minimum weight of the ingredient that is desired in the formula solution.
Number (Formula)
Number is an alias for the formula that ensures compatibility with other systems
Nutrients (tab)
Opt Den
Optimum Density specifies whether or not the solution calculations should find the optimum yield for the diet without having to produce the exact batch weight specified for the formula. If there is a least cost diet that meets the formula's requirements but with a yield lower or higher than the batch weight, then that diet will be the solution regardless of its final yield.
Optimum Density allows the solve algorithm to increase (or decrease) yield in order to find the optimum nutrient density, resulting in a lower cost than solving with the formula's batch weight. Nutrient density is an important tool in feeding animals under conditions of heat or stress.
Two fields control the use of Optimum Density: the optimum density code and the range percentage.
The Optimum Density codes are:
- "Y - Yes" to find the optimum yield
- "N - No" to use the fixed batch weight (the default)
- "W - WeightLimits" to find the optimum yield within specific limits
If you specify "W-weight limits" you should also specify a range percentage. This is the range within which the solution may vary from the specified batch weight. For example if the batch weight is 1000 and the range percentage is 10%, then the solution yield may be anywhere from 900 to 1100.
Helpful hint: The two optimum density codes use a different model for solving than the fixed batch weight model. A code of "W-weight limits" and a range percentage of zero specifies the same batch weight as "N - No", but uses the optimum density model in the solve. This can be useful for cases where the solve has difficulties with "N - No".
Rng%
Optimum Density Range Percent specifies the upper and lower limits for the optimum density calculations when Optimum Density is set to "W - WeightLimits".
For example, if the batch weight is 1000, an Optimum Density Range Percent of 5.00 will constrain the solve to find the optimum yield within a range of 950 to 1050.
Prev Cost
Previous Cost (Formula)
Total ingredient cost of the formula before current Solve Formula.
Ratios
Ratio Specifications consist of a nutrient pair, an ingredient pair, or a nutrient and an ingredient. These are followed by an optional minimum ratio or a maximum ratio (or both).
For example, for a Calcium/Phos ratio of from between 1:1 and 2:1, the following Ratio Specification was entered:
No Name No Name Min Max 32 Calcium % 33 Phos % 1.00 2.00
Ratios can be between nutrients and ingredients, "mix 'em or match 'em".
Round (Formula) Round Code is a one character field that determines how the solution will be rounded.
Enter one of the following:
N (default) does NOT round the ingredients.
R rounds the ingredients exactly to the batch weight (the largest ingredient will have any leftover amounts from rounding the other ingredients).
Y rounds the ingredients without regard to the batch weight.
U rounds the ingredients UP without regard to the batch weight.
Solve Formula
The Solve Formula button creates a new least-cost solution. It updates the Actual (Nutrient amount), Actual Pct (Ingredient), Actual Wgt (Ingredient), Previous Cost (Formula), Total Cost (Formula), Cost (Nutrient), High Cost (Ingredient), Low Cost (Ingredient), and Yield (Formula).
If the Solve Formula calculation is successful, an Optimal Solution message is displayed above the Solve Formula button.
If the Solve Formula calculation is unsuccessful, various Infeasible Solution messages will be displayed above the Solve Formula button.
Species
Formula Species is a MANDATORY field.
The following Species codes are pre-loaded: Beef Dairy Poultry Swine Sheep
Total Cost (Formula)
Total ingredient cost of the formula after Solve Formula.
Type
Formula Type consists of two one-character fields which the user can assign freely.
For example, some users put the initial of the owner of a particular formula here so that other users do not modify it without permission from the owner.
There is one specialized use of these codes for medication interlock codes used by the 3000 series of Wisconsin Electric Manufacturing Co. batch mixers:
Type
1 2 Function
U N Unmedicated - may not follow medicated feed
U Y Unmedicated - may follow medicated feed
M N Medicated - may not follow medicated feed
M Y Medicated – may follow medicated feed
Unit (Formula Nutrient) The units in which the nutrient minimum and maximum values are expressed are determined by the user in the setup area, where nutrients are added or modified. Typical units are ppm (parts per million), mg/kg ( a synonym for parts per million), % (percent -- meaning percent of total weight). % occurs most frequently
Unit expresses a ratio and is often a compound consisting of a fundamental unit of measure or a derived unit of measure divided by another one. Examples of compounds are: mg/kg, IU/lb, mcal/kg.
Examples of fundamental units of measure are lb, g, IU.
Examples of derived units of measure are kg, mcal, mg.
UoM (Formula)
Unit of measure is kg for metric system users and lb for English system users. It is inherited from the setup.
Yield (Formula)
The actual weight of the least-cost solution. The Solve Formula button creates the Yield. It should be the same or very nearly the same as the Batch Weight. If not, the least-cost solution may be infeasible.
When Optimum Density is enabled, the yield may differ greatly from the Batch Weight.
