How to use the saml.signature.algorithm function in saml

$scope.accessType = $scope.accessTypes[2];
        } else if ($scope.client.publicClient) {
            $scope.accessType = $scope.accessTypes[1];
        }
        if ($scope.client.protocol) {
            $scope.protocol = $scope.protocols[$scope.protocols.indexOf($scope.client.protocol)];
        } else {
            $scope.protocol = $scope.protocols[0];
        }
        if ($scope.client.attributes['saml.signature.algorithm'] == 'RSA_SHA1') {
            $scope.signatureAlgorithm = $scope.signatureAlgorithms[0];
        } else if ($scope.client.attributes['saml.signature.algorithm'] == 'RSA_SHA256') {
            $scope.signatureAlgorithm = $scope.signatureAlgorithms[1];
        } else if ($scope.client.attributes['saml.signature.algorithm'] == 'RSA_SHA512') {
            $scope.signatureAlgorithm = $scope.signatureAlgorithms[2];
        } else if ($scope.client.attributes['saml.signature.algorithm'] == 'DSA_SHA1') {
            $scope.signatureAlgorithm = $scope.signatureAlgorithms[3];
        }
        if ($scope.client.attributes['saml_name_id_format'] == 'username') {
            $scope.nameIdFormat = $scope.nameIdFormats[0];
        } else if ($scope.client.attributes['saml_name_id_format'] == 'email') {
            $scope.nameIdFormat = $scope.nameIdFormats[1];
        } else if ($scope.client.attributes['saml_name_id_format'] == 'transient') {
            $scope.nameIdFormat = $scope.nameIdFormats[2];
        } else if ($scope.client.attributes['saml_name_id_format'] == 'persistent') {
            $scope.nameIdFormat = $scope.nameIdFormats[3];
        }
        if ($scope.client.attributes["saml.server.signature"]) {
            if ($scope.client.attributes["saml.server.signature"] == "true") {
                $scope.samlServerSignature = true;
            } else {
                $scope.samlServerSignature = false;

$scope.changeAlgorithm = function() {
        $scope.clientEdit.attributes['saml.signature.algorithm'] = $scope.signatureAlgorithm;
    };