我试图在下面的Ipython Gurobi笔记本中添加库存浓度限制。我以为它会是[m.addConstr（portvars）＆lt; = 0.15，＆＃34; limit＆＃34;）];但我收到一条错误消息（见下面的消息）。任何人都知道如何添加浓度限制？
https://anaconda.org/mcg/markowitz/notebook
TypeError：不支持的操作数类型 - ：＆＃39; bool＆＃39;和＆＃39; NoneType＆＃39;
答案 0 :(得分：0)
Model.addConstr()会占用<?php
// database connection
include 'pdo_config.php';
try {
// new pdo connection
$conn = new PDO($dsn, $user, $pass, $opt);
// post data
$date = $_POST['date'];
$duration = $_POST['duration'];
// Note that the explode only works well if user inputs one blank space to separate the name
// You can try to improve the separation method or better use two different inputs in the form
$nameArray = explode(" ", $_POST['member_name']);
$first_name = $nameArray[0];
$last_name = $nameArray[1];
$statement = $conn->prepare("SELECT member_id FROM members WHERE first_name = :first_name AND last_name = :last_name");
$statement->execute(array(':fisrt_name' => $first_name, ':last_name' => $last_name));
$row = $statement->fetch();
$member_id = $row['member_id'];
// prepare statement and bind parameters
$stmt = $conn->prepare("INSERT INTO games (date, duration, member_id)
VALUES (:date, :duration, :member_id)");
$stmt->bindParam(':date', $date);
$stmt->bindParam(':duration', $duration);
$stmt->bindParam(':member_id', $member_id);
// execute statement
$stmt->execute();
// success or error message
echo "New record created successfully";
}
catch(PDOException $e)
{
echo "Error: " . $e->getMessage();
}
$conn = null;
?>
个对象，因此您可能希望编写类似TempConstr的内容。