Calculation in Modal

Hi,

how i can calc in a Model and give the result back?

Controller:

$ionicModal.fromTemplateUrl('templates/calcs/myModal.html', {
        scope: $scope
    }).then(function(modal) {
        $scope.modal = modal;
    });

HTML:

<ion-modal-view>
    <ion-header-bar class="bar bar-header bar-positive">
        <h1 class="title">Headline</h1>
        <button class="button button-clear button-primary" ng-click="modal.hide()">Cancel</button>
    </ion-header-bar>
    <ion-content class="padding">
        <div class="row">
            <div class="col">
                <label class="item item-input item-stacked-label">
                    <span class="input-label">Radius Millimetre</span>
                    <input type="number" placeholder="0" ng-model="hsCrm">
                </label>

                <label class="item item-input item-stacked-label">
                    <span class="input-label">Length Millimetre</span>
                    <input type="number" placeholder="0" ng-model="hsClm">
                </label>
            </div>
        </div>
    </ion-content>
</ion-modal-view>